Merge branch '4.2RC'4.2

2 files changed, 166 insertions, 106 deletions

diff --git a/doc/admin/administrator_guide.md b/doc/admin/administrator_guide.md
index 2b1c84180..c884bb0bd 100644
--- a/doc/admin/administrator_guide.md
+++ b/doc/admin/administrator_guide.md
@@ -1,4 +1,3 @@
-
 ### Overview
 
 $Projectname is more than a simple web application. It is a
@@ -17,48 +16,47 @@ such as XAMPP and WAMP are not officially supported at this time however
 we welcome patches if you manage to get it working.
 
 ### Where to find more help
-If you encounter problems or have issues not addressed in this documentation, 
+If you encounter problems or have issues not addressed in this documentation,
 please let us know via the [Github issue
 tracker](https://framagit.org/hubzilla/core/issues). Please be as clear as you
 can about your operating environment and provide as much detail as possible
 about any error messages you may see, so that we can prevent it from happening
 in the future. Due to the large variety of operating systems and PHP platforms
 in existence we may have only limited ability to debug your PHP installation or
-acquire any missing modules * but we will do our best to solve any general code
+acquire any missing modules, but we will do our best to solve any general code
 issues.
 
-### Before you begin 
+### Before you begin
 
 #### Choose a domain name or subdomain name for your server
 
-$Projectname can only be installed into the root of a domain or sub-domain, and can 
+$Projectname can only be installed into the root of a domain or sub-domain, and can
 not be installed using alternate TCP ports.
 
 #### Decide if you will use SSL and obtain an SSL certificate before software installation
 
-You SHOULD use SSL. If you use SSL, you MUST use a "browser-valid" certificate.  
+You SHOULD use SSL. If you use SSL, you MUST use a "browser-valid" certificate.
 *You MUST NOT use self-signed certificates!*
 
-Please test your certificate prior to installation. A web tool for testing your 
-certificate is available at "http://www.digicert.com/help/". When visiting your 
-site for the first time, please use the SSL ("https://") URL if SSL is available. 
-This will avoid problems later. The installation routine will not allow you to 
+Please test your certificate prior to installation. A web tool for testing your
+certificate is available at "http://www.digicert.com/help/". When visiting your
+site for the first time, please use the SSL ("https://") URL if SSL is available.
+This will avoid problems later. The installation routine will not allow you to
 use a non browser-valid certificate.
 
-
-This restriction is incorporated because public posts from you may contain 
+This restriction is incorporated because public posts from you may contain
 references to images on your own hub. Other members viewing their stream on
 other hubs will get warnings if your certificate is not trusted by their web
 browser. This will confuse many people because this is a decentralised network
-and they will get the warning about your hub while viewing their own hub and may 
-think their own hub has an issue. These warnings are very technical and scary to 
+and they will get the warning about your hub while viewing their own hub and may
+think their own hub has an issue. These warnings are very technical and scary to
 some folks, many of whom will not know how to proceed except to follow the browser
 advice. This is disruptive to the community. That said, we recognise the issues
 surrounding the current certificate infrastructure and agree there are many
-problems, but that doesn't change the requirement. 
+problems, but that doesn't change the requirement.
 
 Free "browser-valid" certificates are available from providers such as StartSSL
-and LetsEncrypt. 
+and LetsEncrypt.
 
 If you do NOT use SSL, there may be a delay of up to a minute for the initial
 install script - while we check the SSL port to see if anything responds there.
@@ -66,11 +64,11 @@ When communicating with new sites, $Projectname always attempts connection on th
 SSL port first, before falling back to a less secure connection.  If you do not
 use SSL, your webserver MUST NOT listen on port 443 at all.
 
-If you use LetsEncrypt to provide certificates and create a file under 
-.well-known/acme-challenge so that LetsEncrypt can verify your domain ownership, 
-please remove or rename the .well-known directory as soon as the certificate is 
+If you use LetsEncrypt to provide certificates and create a file under
+.well-known/acme-challenge so that LetsEncrypt can verify your domain ownership,
+please remove or rename the .well-known directory as soon as the certificate is
 generated. $Projectname will provide its own handler for ".well-known" services when
-it is installed, and an existing directory in this location may prevent some of 
+it is installed, and an existing directory in this location may prevent some of
 these services from working correctly. This should not be a problem with Apache,
 but may be an issue with nginx or other web server platforms.
 
@@ -82,20 +80,20 @@ There are several ways to deploy a new hub.
 * Automated deployment using an OpenShift virtual private server (VPS)
 
 ### Requirements
-* Apache with mod-rewrite enabled and "AllowOverride All" so you can use a 
+* Apache with mod-rewrite enabled and "AllowOverride All" so you can use a
   local .htaccess file. Some folks have successfully used nginx and lighttpd.
   Example config scripts are available for these platforms in doc/install.
-  Apache and nginx have the most support. 
+  Apache and nginx have the most support.
 
-* PHP 5.5 or later. 
- * Note that on some shared hosting environments, the _command line_ version of 
-PHP might differ from the _webserver_ version
+* PHP 7.1 or later.
+ * Note that on some shared hosting environments, the _command line_
+   version of PHP might differ from the _webserver_ version
 
-* PHP *command line* access with register_argc_argv set to true in the 
-  php.ini file * and with no hosting provider restrictions on the use of 
+* PHP *command line* access with register_argc_argv set to true in the
+  php.ini file * and with no hosting provider restrictions on the use of
   exec() and proc_open().
 
-* curl, gd (with at least jpeg and png support), mysqli, mbstring, mcrypt, zip, 
+* curl, gd (with at least jpeg and png support), mysqli, mbstring, mcrypt, zip,
   and openssl extensions. The imagick extension is not required but desirable.
 
 * xml extension is required if you want webdav to work.
@@ -106,7 +104,7 @@ PHP might differ from the _webserver_ version
 
 * ability to schedule jobs with cron.
 
-* Installation into a top-level domain or sub-domain (without a 
+* Installation into a top-level domain or sub-domain (without a
   directory/path component in the URL) is REQUIRED.
 
 ### Manual Installation
@@ -115,9 +113,9 @@ PHP might differ from the _webserver_ version
 If you copy the directory tree to your webserver, make sure that you include the
 hidden files like .htaccess.
 
-If you are able to do so, we recommend using git to clone the source 
-repository rather than to use a packaged tar or zip file.  This makes the 
-software much easier to update. The Linux command to clone the repository 
+If you are able to do so, we recommend using git to clone the source
+repository rather than to use a packaged tar or zip file.  This makes the
+software much easier to update. The Linux command to clone the repository
 into a directory "mywebsite" would be:
 
     git clone https://framagit.org/hubzilla/core.git mywebsite
@@ -126,7 +124,7 @@ and then you can pick up the latest changes at any time with:
 
     git pull
 
-make sure folders ``store/[data]/smarty3`` and ``store`` exist and are 
+make sure folders ``store/[data]/smarty3`` and ``store`` exist and are
 writable by the webserver:
 
     mkdir -p "store/[data]/smarty3"
@@ -150,7 +148,7 @@ web-based administrative tools to function:
 
 #### Official addons
 ##### Installation
-Navigate to your website. Then you should clone the addon repository (separately). We'll give this repository a nickname of 'hzaddons'. You can pull in other hubzilla addon repositories by giving them different nicknames::
+Navigate to your website. Then you should clone the addon repository (separately). We'll give this repository a nickname of 'hzaddons'. You can pull in other hubzilla addon repositories by giving them different nicknames:
 
     cd mywebsite
     util/add_addon_repo https://framagit.org/hubzilla/addons.git hzaddons
@@ -161,9 +159,9 @@ For keeping the addon tree updated, you should be on your top level website dire
     cd mywebsite
     util/update_addon_repo hzaddons
 
-Create searchable representations of the online documentation. You may do this 
-any time that the documentation is updated :  
-    
+Create searchable representations of the online documentation. You may do this
+any time that the documentation is updated :
+
     cd mywebsite
     util/importdoc
 
@@ -203,45 +201,28 @@ We recommend the following addons be installed on all public sites:
 
 Several web communities have begun to converge using common protocols. The protocols involved are somewhat limited in their abilities. The GNU-Social protocol for instance offers no privacy modes, and the Diaspora protocol is somewhat restrictive in what kinds of communications are allowed. All comments must be signed in a very unique manner by the original author. The ActivityPub protocol is also being considered and may be supported at a future date. No other existing protocol supports nomadic location as used by this project. This presents some support challenges as some features work with some networks and don't work with others. Nevertheless the federation protocols allow connections to be made to a much larger community of people worldwide. They are provided as addons.
 
-> diaspora - The Diaspora Protocol used by Diaspora and Friendica. You should enable 'Diaspora Statistics' (statistics) first to enable all the available features. 
+* diaspora - The Diaspora Protocol used by Diaspora and Friendica. You should enable 'Diaspora Statistics' (statistics) first to enable all the available features.
 
-> gnusoc - The GNU-Social Protocol, used by GNU-Social, Mastodon and several other communities. This addon requires you first install the 'pubsubhubbub' service (also an addon). 
+* gnusoc - The GNU-Social Protocol, used by GNU-Social, Mastodon and several other communities. This addon requires you first install the 'pubsubhubbub' service (also an addon).
 
 Each member of your site must choose whether or not to allow these protocols individually as they may conflict with several desirable core features and abilities of this software (such as channel migration and cloning). They do this from their 'Settings -> Feature/Addon Settings' page. The administrator may also set the following:
 
 	util/config system.diaspora_allowed 1
 	util/config system.gnusoc_allowed 1
 
-and enable these protocols automatically for all newly created channels. 
-
-
-
-  
-
-
-### Techlevels
-
-We've implemented several different mechanisms in order to reduce the apparent complexity and learning curve presented to new members. At the same time, we do not wish to limit any functionality for people who are able to grasp some slightly advanced technical technical features. The first mechanism was to move several features to an optional 'Features' page where they could be enabled at will; with the default interface kept somewhat lean. 
-
-The problem we had now is that the number of features began to grow dramatically, and the Feature page is daunting in possibilities. There are also features present which probably should not be available to all members, but may be extremely useful to those with technical backgrounds.
-
-The techlevels seeeks to remedy this by grouping features within different levels of technical ability; starting at 0 (uncomfortable with technology), and up to 5 (Unix wizard or equivalent).
-
-When a new member registers, their account is provided a techlevel setting of 0. On the account settings page they may change this to any available level. A higher level opens more advanced features and possible interactions.
-
-The account administrator may also lock a particular level, lock a maximum level, or change/re-arrange the features available to any level. Those with the minimum level are typically not very exploratory and are unlikely to discover the advanced modes. This is by design. Those that look around and desire more interactions will find them. In the absence of administrator defaults they may choose any level. As they look at the features available to the level in question, it is generally expected that they will discover some features are beyond their comprehension and it is hoped they will back off to a level where the interface and features are comfortable to their skill level. 
+and enable these protocols automatically for all newly created channels.
 
 ### Service Classes
 
 Service classes allow you to set limits on system resources by limiting what individual
-accounts can do, including file storage and top-level post limits. Define custom service 
-classes according to your needs in the `.htconfig.php` file. For example, create 
+accounts can do, including file storage and top-level post limits. Define custom service
+classes according to your needs in the `.htconfig.php` file. For example, create
 a _standard_ and _premium_ class using the following lines:
 
     // Service classes
-    
+
     App::$config['system']['default_service_class']='standard'; // this is the default service class that is attached to every new account
-    
+
     // configuration for standard service class
     App::$config['service_class']['standard'] =
     array('photo_upload_limit'=>2097152, // total photo storage limit per channel (here 2MB)
@@ -251,7 +232,7 @@ a _standard_ and _premium_ class using the following lines:
     'total_channels' =>100, // number of channels the user can add, other users can still add this channel, even if the limit is reached
     'attach_upload_limit' =>2097152, // total attachment storage limit per channel (here 2MB)
     'chatters_inroom' =>20);
-    
+
     // configuration for premium service class
     App::$config['service_class']['premium'] =
     array('photo_upload_limit'=>20000000000, // total photo storage limit per channel (here 20GB)
@@ -262,7 +243,7 @@ a _standard_ and _premium_ class using the following lines:
     'attach_upload_limit' =>20000000000, // total attachment storage limit per channel (here 20GB)
     'chatters_inroom' =>100);
 
-To apply a service class to an existing account, use the command line utility from the 
+To apply a service class to an existing account, use the command line utility from the
 web root:
 
 `util/service_class`
@@ -298,11 +279,11 @@ set the account that owns channel 'blogchan' to service class 'firstclass' (with
 * access_tokens - maximum number of Guest Access Tokens per channel
 
 ### Theme management
-#### Repo management example 
+#### Repo management example
 1. Navigate to your hub web root
 
   ```
-  root@hub:/root# cd /var/www 
+  root@hub:/root# cd /var/www
   ```
 2. Add the theme repo and give it a name
 
@@ -319,70 +300,136 @@ set the account that owns channel 'blogchan' to service class 'firstclass' (with
 
 #### Keywords
 
-There is a "tag cloud" of keywords that can appear on the channel directory page. 
-If you wish to hide these keywords, which are drawn from the directory server, you 
+There is a "tag cloud" of keywords that can appear on the channel directory page.
+If you wish to hide these keywords, which are drawn from the directory server, you
 can use the *config* tool:
 
     util/config system disable_directory_keywords 1
-    
-If your hub is in the standalone mode because you do not wish to connect to the 
-global grid, you may instead ensure the the _directory_server_ system option is 
+
+If your hub is in the standalone mode because you do not wish to connect to the
+global grid, you may instead ensure the the _directory_server_ system option is
 empty:
 
     util/config system directory_server ""
 
-
 ### Administration
 
 #### Site Administration
 
-Administration of the website is commonly done through the admin webpage located at /admin on your website. In order to access this page you must have administration rights to the server. Administration rights are granted to the first account to register on your site, **provided** the email address of that account exactly matches the email address you provided as the administrator's email address during setup. 
+Administration of the website is commonly done through the admin webpage located at /admin on your website. In order to access this page you must have administration rights to the server. Administration rights are granted to the first account to register on your site, **provided** the email address of that account exactly matches the email address you provided as the administrator's email address during setup.
 
-There are several ways that this can fail and leave the system without an administrator account, for instance if the first account that was created provided a different email address than the administrator email address that was supplied during setup. 
+There are several ways that this can fail and leave the system without an administrator account, for instance if the first account that was created provided a different email address than the administrator email address that was supplied during setup.
 
 For security reasons there is no web page or interface on the system which will give you administrator access. If you need to correct a situation where a system has no administrator account it **must** be done by editing the account table in the database. There is no other way. To do this, you will need to locate the entry in the account table which belongs to the desired administrator, and set 'account_roles' for that entry to 4096. You will then be able to access the admin page from your system's profile menu or directly via /admin .
 
-A hub can have multiple admins and there is no limit to how administrators you can have. Repeat the above process for every account you wish to provide with administration rights.   
-
+A hub can have multiple admins and there is no limit to how administrators you can have. Repeat the above process for every account you wish to provide with administration rights.
 
 ### Troubleshooting
 
 #### Log files
 
-The system logfile is an extremely useful resource for tracking down things that go wrong. This can be enabled in the admin/log configuration page. A loglevel setting of LOGGER_DEBUG is preferred for stable production sites. Most things that go wrong with communications or storage are listed here. A setting of LOGGER_DATA provides [b]much[/b] more detail, but may fill your disk. In either case we recommend the use of logrotate on your operating system to cycle logs and discard older entries. 
-
-At the bottom of your .htconfig.php file are several lines (commented out) which enable PHP error logging. This reports issues with code syntax and executing the code and is the first place you should look for issues which result in a "white screen" or blank page. This is typically the result of code/syntax problems. 
-Database errors are reported to the system logfile, but we've found it useful to have a file in your top-level directory called dbfail.out which [b]only[/b] collects database related issues. If the file exists and is writable, database errors will be logged to it as well as to the system logfile.
-
-In the case of "500" errors, the issues may often be logged in your webserver logs, often /var/log/apache2/error.log or something similar. Consult your operating system documentation. 
+The system logfile is an extremely useful resource for tracking down
+things that go wrong. This can be enabled in the admin/log
+configuration page. A loglevel setting of `LOGGER_DEBUG` is preferred
+for stable production sites. Most things that go wrong with
+communications or storage are listed here. A setting of LOGGER_DATA
+provides *much* more detail, but may fill your disk. In either
+case we recommend the use of logrotate on your operating system to
+cycle logs and discard older entries.
+
+At the bottom of your .htconfig.php file are several lines (commented
+out) which enable PHP error logging. This reports issues with code
+syntax and executing the code and is the first place you should look
+for issues which result in a "white screen" or blank page. This is
+typically the result of code/syntax problems.  Database errors are
+reported to the system logfile, but we've found it useful to have a
+file in your top-level directory called dbfail.out which *only*
+collects database related issues. If the file exists and is writable,
+database errors will be logged to it as well as to the system logfile.
+
+In the case of "500" errors, the issues may often be logged in your
+webserver logs, often /var/log/apache2/error.log or something
+similar. Consult your operating system documentation.
 
 There are three different log facilities.
 
-**The first is the database failure log**. This is only used if you create a file called specifically 'dbfail.out' in the root folder of your website and make it write-able by the web server. If we have any database failed queries, they are all reported here. They generally indicate typos in our queries, but also occur if the database server disconnects or tables get corrupted. On rare occasions we'll see race conditions in here where two processes tried to create an xchan or cache entry with the same ID. Any other errors (especially persistent errors) should be investigated.
-
-**The second is the PHP error log**. This is created by the language processor and only reports issues in the language environment. Again these can be syntax errors or programming errors, but these generally are fatal and result in a "white screen of death"; e.g. PHP terminates. You should probably look at this file if something goes wrong that doesn't result in a white screen of death, but it isn't uncommon for this file to be empty for days on end.
-
-There are some lines at the bottom of the supplied .htconfig.php file; which if uncommented will enable a PHP error log (*extremely* useful for finding the source of white screen failures). This isn't done by default due to potential issues with logfile ownership and write permissions and the fact that there is no logfile rotation by default.                                                                                                          
-                                                                                                                  
-
-**The third is the "application log"**. This is used by $Projectname to report what is going on in the program and usually reports any difficulties or unexpected data we received. It also occasionally reports "heartbeat" status messages to indicate that we reached a certain point in a script. **This** is the most important log file to us, as we create it ourself for the sole purpose of reporting the status of background tasks and anything that seems weird or out of place. It may not be fatal, but maybe just unexpected. If you're performing a task and there's a problem, let us know what is in this file when the problem occurred. (Please don't send me 100M dumps you'll only piss me off). Just a few relevant lines so I can rule out a few hundred thousand lines of code and concentrate on where the problem starts showing up.
+**The first is the database failure log**. This is only used if you
+  create a file called specifically `dbfail.out` in the root folder of
+  your website and make it write-able by the web server. If we have
+  any database failed queries, they are all reported here. They
+  generally indicate typos in our queries, but also occur if the
+  database server disconnects or tables get corrupted. On rare
+  occasions we'll see race conditions in here where two processes
+  tried to create an xchan or cache entry with the same ID. Any other
+  errors (especially persistent errors) should be investigated.
+
+**The second is the PHP error log**. This is created by the language
+  processor and only reports issues in the language environment. Again
+  these can be syntax errors or programming errors, but these
+  generally are fatal and result in a "white screen of death";
+  e.g. PHP terminates. You should probably look at this file if
+  something goes wrong that doesn't result in a white screen of death,
+  but it isn't uncommon for this file to be empty for days on end.
+
+  There are some lines at the bottom of the supplied `.htconfig.php`
+  file; which if uncommented will enable a PHP error log (*extremely*
+  useful for finding the source of white screen failures). This isn't
+  done by default due to potential issues with logfile ownership and
+  write permissions and the fact that there is no logfile rotation by
+  default.
+
+**The third is the "application log"**. This is used by $Projectname
+  to report what is going on in the program and usually reports any
+  difficulties or unexpected data we received. It also occasionally
+  reports "heartbeat" status messages to indicate that we reached a
+  certain point in a script. **This** is the most important log file
+  to us, as we create it ourself for the sole purpose of reporting the
+  status of background tasks and anything that seems weird or out of
+  place. It may not be fatal, but maybe just unexpected. If you're
+  performing a task and there's a problem, let us know what is in this
+  file when the problem occurred. (Please don't send me 100M dumps
+  you'll only piss me off). Just a few relevant lines so I can rule
+  out a few hundred thousand lines of code and concentrate on where
+  the problem starts showing up.
+
+These are your site logs, not mine. We report serious issues at any
+log level. I highly recommend `DEBUG` log level for most sites - which
+provides a bit of additional info and doesn't create huge
+logfiles. When there's a problem which defies all attempts to track,
+you might wish to use `DATA` log level for a short period of time to
+capture all the detail of what structures we were dealing with at the
+time. This log level will use a lot of space so is recommended only
+for brief periods or for developer test sites.
+
+I recommend configuring logrotate for both the php log and the
+application log. I usually have a look at dbfail.out every week or
+two, fix any issues reported and then starting over with a fresh
+file. Likewise with the PHP logfile. I refer to it once in a while to
+see if there's something that needs fixing.
+
+If something goes wrong, and it's not a fatal error, I look at the
+application logfile. Often I will
 
-These are your site logs, not mine. We report serious issues at any log level. I highly recommend 'DEBUG' log level for most sites - which provides a bit of additional info and doesn't create huge logfiles. When there's a problem which defies all attempts to track, you might wish to use DATA log level for a short period of time to capture all the detail of what structures we were dealing with at the time. This log level will use a lot of space so is recommended only for brief periods or for developer test sites.
-
-I recommend configuring logrotate for both the php log and the application log. I usually have a look at dbfail.out every week or two, fix any issues reported and then starting over with a fresh file. Likewise with the PHP logfile. I refer to it once in a while to see if there's something that needs fixing.
-
-If something goes wrong, and it's not a fatal error, I look at the application logfile. Often I will
 ```
-tail -f logfile.out 
+tail -f logfile.out
 ```
 
-While repeating an operation that has problems. Often I'll insert extra logging statements in the code if there isn't any hint what's going wrong. Even something as simple as "got here" or printing out the value of a variable that might be suspect. You can do this too - in fact I encourage you to do so. Once you've found what you need to find, you can
+While repeating an operation that has problems. Often I'll insert
+extra logging statements in the code if there isn't any hint what's
+going wrong. Even something as simple as "got here" or printing out
+the value of a variable that might be suspect. You can do this too -
+in fact I encourage you to do so. Once you've found what you need to
+find, you can
 
 ```
 git checkout file.php
 ```
 
-To immediately clear out all the extra logging stuff you added.  Use the information from this log and any detail you can provide from your investigation of the problem to file your bug report - unless your analysis points to the source of the problem. In that case, just fix it. 
+To immediately clear out all the extra logging stuff you added.  Use
+the information from this log and any detail you can provide from your
+investigation of the problem to file your bug report - unless your
+analysis points to the source of the problem. In that case, just fix
+it.
 
 ##### Rotating log files
 
@@ -390,13 +437,25 @@ To immediately clear out all the extra logging stuff you added.  Use the informa
 1. Create a directory in your web root called `log` with webserver write permissions
 1. Go to the **logrot** admin settings and enter this folder name as well as the max size and number of retained log files.
 
-
 #### Reporting issues
 
-When reporting issues, please try to provide as much detail as may be necessary for developers to reproduce the issue and provide the complete text of all error messages.
-
-We encourage you to try to the best of your abilities to use these logs combined with the source code in your possession to troubleshoot issues and find their cause. The community is often able to help, but only you have access to your site logfiles and it is considered a security risk to share them.   
-
-If a code issue has been uncovered, please report it on the project bugtracker (https://framagit.org/hubzilla/core/issues). Again provide as much detail as possible to avoid us going back and forth asking questions about your configuration or how to duplicate the problem, so that we can get right to the problem and figure out what to do about it. You are also welcome to offer your own solutions and submit patches. In fact we encourage this as we are all volunteers and have little spare time available. The more people that help, the easier the workload for everybody. It's OK if your solution isn't perfect. Every little bit helps and perhaps we can improve on it. 
-
-
+When reporting issues, please try to provide as much detail as may be
+necessary for developers to reproduce the issue and provide the
+complete text of all error messages.
+
+We encourage you to try to the best of your abilities to use these
+logs combined with the source code in your possession to troubleshoot
+issues and find their cause. The community is often able to help, but
+only you have access to your site logfiles and it is considered a
+security risk to share them.
+
+If a code issue has been uncovered, please report it on the project
+bugtracker (https://framagit.org/hubzilla/core/issues). Again provide
+as much detail as possible to avoid us going back and forth asking
+questions about your configuration or how to duplicate the problem, so
+that we can get right to the problem and figure out what to do about
+it. You are also welcome to offer your own solutions and submit
+patches. In fact we encourage this as we are all volunteers and have
+little spare time available. The more people that help, the easier the
+workload for everybody. It's OK if your solution isn't perfect. Every
+little bit helps and perhaps we can improve on it.
diff --git a/doc/hidden_configs.bb b/doc/hidden_configs.bb
index 8b5429deb..dc3906df1 100644
--- a/doc/hidden_configs.bb
+++ b/doc/hidden_configs.bb
@@ -51,6 +51,7 @@ Options are:
   [*= system.email_notify_icon_url ] URL of image (32x32) to display in email notifications (HTML bodies).
   [*= system.expire_delivery_reports ] Expiration in days for delivery reports - default 10
   [*= system.expire_limit ] Don't expire any more than this number of posts per channel per expiration run to keep from exhausting memory. Default 5000.
+  [*= system.filesystem_storage_thumbnails ] If '1', use filesystem instead SQL database to store thumbnails. Default is '0'. Introduced in 4.2
   [*= system.hidden_version_siteinfo ] If true, do not report the software version on siteinfo pages (system.hide_version also hides the version on these pages, this setting *only* hides the version on siteinfo pages).
   [*= system.hide_help ] Don't display help documentation link in nav bar
   [*= system.hide_in_statistics ] Tell the red statistics servers to completely hide this hub in hub lists.
@@ -79,7 +80,7 @@ Options are:
   [*= system.startpage ] Set the default page to be taken to after a login for all channels at this website.  Can be overwritten by user settings.
   [*= system.sys_expire_days ] How many days to keep discovered public content from other sites
   [*= system.taganyone ] Allow the @mention tagging of anyone whether you are connected or not.
-  [*= system.tempdir ] Place to store temporary files (currently unused), default is defined in the PHP configuration  
+  [*= system.tempdir ] Place to store temporary files (currently unused), default is defined in the PHP configuration.
   [*= system.tos_url ] Set an alternative link for the ToS location.
   [*= system.transport_security_header ] if non-zero and SSL is being used, include a strict-transport-security header on webpages
   [*= system.uploaddir ] Location to upload files (default is system.tempdir, currently used only by js_upload plugin)