Dialog performance drastically decreased since 6.11

I hoped that 6.13. would improve but the dialog performance of PL is still much worse than before. I have nothing changed but in opposite to earlier versions it takes always seconds until any change is applied/visible in preview.
Whats wrong?

Have you tried to delete the cache in DPL’s preference settingś last tab?

If this does not help, deleting PhotoLab’s database could do the trick. Be sure to check for consequences before you delete the DB … and keep a copy of the DB for fallback.

Thank you, Playtypus, will try the first advice (is 1GB right now) but do not know how to delete the DB in case it needs to.

I can confirm that deleting the cache was of good help. Thanks a lot, will observe and forget about the DB deletion.
Thanks again, Cheers!