LocalSettings.php is MediaWiki's central configuration file for a wiki. Should you read about and wish to make a configuration change to your wiki that will require the modification of your wiki's LocalSettings.php, please visit the Self Service portal to see if the action can be done there. If not, please open a ticket with our Support department and we will gladly assist you with your change.
You may choose to include a link to the MediaWiki page of the action you'd like us to take. This is not necessary, however.
There is also no need to include the actual PHP code you'd like us to add to your LocalSettings.php, as the way we may configure such a change may be done differently due to security or functionality concerns. If you are not at all familiar with computer code, please do not provide code from MediaWiki.org, as the code you provide might not be what you actually wanted, or actually conflict with your desired change. Instead, we recommend you provide an English language description of the desired changes, with which we can more definitively assist you. (If you are familiar with PHP code and find it easier than describing the proposed changes using words, by all means we welcome it, but please indicate that you are a coder, so that we may better assist you and use technical terminology with you, if we need to do so.)
Disclaimer: Not all changes requested will be made. If our support team deems a proposed change to be malicious, harmful, unreasonable, imprudent, or technically impossible, or finds it violates the Terms of Service, the change will not be made and a reason behind the denial will be provided. However, very few requests fall under this category.