TYPO3 Core

The Install Tool in 4.4 can run in two skin modes. One for being loaded in the backend (light) and one for being loaded as "standalone" (dark).

Currently, if you load the standalone version first and then login to the backend and load the Install Tool from there, it will use the design skin of the standalone (dark).

The detection is currently session based and does only happen on the initial load. As soon as the session is created there will be no more checks for which environment the Install Tool is running in.

Solution:

Switch to a JS only approach that checks if the current document location is the same as the top location, meaning, is the document loaded in a frame or not. If it is not loaded in a frame, the body gets a class="standalone" added which equals to the re-factored CSS.
(issue imported from #M14365)