In light of your previous post on the DevPrev memory leak...

https://fold.it/portal/node/2011044

...this means that the game is now mostly unplayable by anyone with the most recent DevPrev update.

Not good.

Not sure about the "unplayable" part, but the game is kind of unresponsive lately. When I click on a taskbar icon, the window either doesn't display, or shows with a tiny squashed screen image in the upper left corner. Eventually, the screen displays, but it takes patience.

The sluggishness is especially noticeable on my ancient laptop, but it's pretty much the same on my slightly newer desktop.

I just went through evaluating a new high-end laptop, with a Xeon W-10855M processor and a UHD (3840 x 2160) display. While it was nice being able to run recipes more quickly, the responsiveness issues were even worse. I usually couldn't get a minimized window to display at all. I resorted to using Processor Explorer, right-clicking the Foldit client in the process list, then selecting Window -> Maximize to see the window again. I'm not sure if that was a function of the display size or other issues.

(While the processing power was nice, the laptop had issues with extreme fan noise and heat, and I ended up returning it yesterday.)

Loci, you might want to file a different feedback on that issue, as it is unrelated to this one.

This one is about being unable to revert to main client because of a version identification issue. The client still works, but remains the january devprev program.

We can't reproduce this on our end.

Can you verify that a new install works?

You could also try moving/renaming the following files:

version-binary.txt
version-database.txt
version-resources.txt

And that should force it to re-download the components.

I have deleted those files and restarted foldit.
I now see an old (white background startscreen) client start and subsequently crash over and over.
What do I do now ?