Could it be considered to use another filemanager for the ckEditor
Possible: yes. Easy: no.
gpFinder is tightly integrated and adapted to the CMS. It does some required things, other filemanagers cannot do out-of-the-box.
So, it would need a considerable affort to implement and maintain it.
But, although not trivial, gpFinder's CSS could be altered to get something very similar to responsive filemanager.
Possible: yes. Easy: hmmm ;-)
RFM is licensed under Attribution-NonCommercial 3.0 Unported (CC BY-NC 3.0) which states..
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