There are some config values that haven't found their way into the administration page.
This has several reasons.
Maybe they are part of a current development that isn't considered stable and will be added later in the administration page when it is considered safe.
Or it triggers something that isn't expected to be of public interest. Or it is for testing purposes only.
* **auth_cookie_lifetime** (Integer) - Number of days that should pass without any activity before a user who chose "Remember me" when logging in is considered logged out. Defaults to 7.
* **local_search** (Boolean) - Blocks search for users who are not logged in to prevent crawlers from blocking your system.
* **max_connections** - The maximum number of database connections which can be in use before the poller process is deferred to it's next interval. When the system can't detect the maximum numbers of connection then this value can be used.
* **max_connections_level** - The maximum level of connections that are allowed to let the poller start. It is a percentage value. Default value is 75.
* **max_contact_queue** - Default value is 500.
* **max_batch_queue** - Default value is 1000.
* **max_processes_backend** - Maximum number of concurrent database processes for background tasks. Default value is 5.
* **max_processes_frontend** - Maximum number of concurrent database processes for foreground tasks. Default value is 20.
* **profiler** (Boolean) - Enable internal timings to help optimize code. Needed for "rendertime" addon. Default is false.
* **free_crawls** - Number of "free" searches when "permit_crawling" is activated (Default value is 10)
* **crawl_permit_period** - Period in seconds between allowed searches when the number of free searches is reached and "permit_crawling" is activated (Default value is 60)
* **png_quality** - Default value is 8.
* **proc_windows** (Boolean) - Should be enabled if Friendica is running under Windows.
* **proxy_cache_time** - Time after which the cache is cleared. Default value is one day.
* **pushpoll_frequency** -
* **qsearch_limit** - Default value is 100.
* **relay_server** - Experimental Diaspora feature. Address of the relay server where public posts should be send to. For example https://podrelay.net
* **relay_subscribe** (Boolean) - Enables the receiving of public posts from the relay. They will be included in the search and on the community page when it is set up to show all public items.
* **relay_scope** - Can be "all" or "tags". "all" means that every public post should be received. "tags" means that only posts with selected tags should be received.
* **relay_server_tags** - Comma separated list of tags for the "tags" subscription (see "relay_scrope")
* **relay_user_tags** (Boolean) - If enabled, the tags from the saved searches will used for the "tags" subscription in addition to the "relay_server_tags".
* **remove_multiplicated_lines** (Boolean) - If enabled, multiple linefeeds in items are stripped to a single one.
* **show_unsupported_addons** (Boolean) - Show all addons including the unsupported ones.
* **show_unsupported_themes** (Boolean) - Show all themes including the unsupported ones.
* **throttle_limit_day** - Maximum number of posts that a user can send per day with the API.
* **throttle_limit_week** - Maximum number of posts that a user can send per week with the API.
* **throttle_limit_month** - Maximum number of posts that a user can send per month with the API.
* **wall-to-wall_share** (Boolean) - Displays forwarded posts like "wall-to-wall" posts.
* **worker_cooldown** - Cooldown time after each worker function call. Default value is 0 seconds.
* **xrd_timeout** - Timeout for fetching the XRD links. Default value is 20 seconds.