Solutions, features, and CompatibilityLevel

I recently came across an issue where certain feature definitions were not available in 2010 mode sites in one farm, but they were in another. It turned out that the parameters supplied to Install-SPSolution are the reason. Essentially, the difference was specifying -CompatibilityLevel {14,15} vs specifying nothing. I found this article to be very helpful: Planning Deployment of Farm Solutions for SharePoint 2013

Get all features that define Site Settings links

Recently, I needed to find out where a particular link listed under Site Settings. Doing a bit of research on how to add links to a Site Settings page involves defining a CustomAction in the Elements.xml file with a Location of Microsoft.SharePoint.SiteSettings. Reversing this logic, we can find all Elements.xml files that contains a line Location="Microsoft.SharePoint.SiteSettings" and from there work backwards to get the SharePoint feature.

Here is a Powershell that does this:
Get-ChildItem -Recurse -Filter *.xml | Select-String -Pattern 'Microsoft.SharePoint.SiteSettings' | Group-Object path | ForEach-Object {$x = $_.Name; Get-SPFeature | Where-Object {$x -like "$($_.RootDirectory)*"}} | Format-Table Id, Scope, @{l='Title';e={$_.GetTitle(1033)}} -AutoSize

This script can easily be modified to find other menu items by changing the Select-String -Pattern to something else such as Microsoft.SharePoint.StandardMenu.