You might want to try Lightzone (IMO it is a more professional tool for photographers than lightroom and it has a native linux version)
There is only one problem...
It used to be free of charge for linux. They don't do it for free anymore
It's a beta trial version.
I used to use the free version of it. I love the program. Unfortunately, I reinstalled my system and could not find the .bin file with the free version of Lightzone. I'm forced to use the trial version now
btw, has anyone got the installation file of Lightzone version 2.4 (it was free to download)?