Does the upgrade from macOS 10.12 Sierra to macOS 10.13 High Sierra remove any extensions, kernel extensions, Applications or settings that are known to be incompatible or disabled?
I looked briefly at /var/log/install.log
and see there are over 20,000 lines of things that were logged during the migration and it looks like a lot of things were moved to /Volumes/whatever/Recovered Items but that directory is now deleted and cleaned up.
Additionally, there appears to be a runtime check of this: Sep 10 16:53:56 MacBook osinstallersetupd[514]: Retrieved package com.apple.pkg.CompatibilityUpdate (http://swcdn.apple.com/content/downloads/47/49/031-75970/fhywgjppj47p6n4udnsqtyszmwfwjt78aj/OSX_10_12_IncompatibleAppList.pkg)
package that now has a 404 not found error.
Are there places to look for what was removed from a specific Mac post upgrade if there's not a more comprehensive list of things we can check before an upgrade?