Programs unloading from memory (or crashing) randomly, Firefox freezes occasionally.

I’m on the latest version of Tumbleweed, and noticed programs often randomly unload from memory (more likely crash, but I’m not sure), Firefox often freezes, becomes extremely unresponsive.
A few examples:
I had Kate Text Editor open, was actively writing and editing text files, Terminal with two tabs was open, I started Firefox to look something up, but when returned back to Kate, I noticed all my text files were gone, as if Kate had just started. When attempting to open previous files, Kate informs me “the file was not closed properly - view changes; recover data; discard”. I recover and continue working, open Firefox, Kate, Terminal, back and forth, then return to Terminal, and notice it unloaded as well, tabs were closed.
Firefox freezes randomly, I noticed especially when I’m writing and editing text - copying, pasting, selecting words, sentences, switching between tabs, and then it just freezes, and there’s nothing you can but to restart the browser.

I have another unrelated, but similar problem with KDE Desktop Sessions. If after reboot you don’t wait long enough for a Session to be restored, and for example start Kate, open text file and start editing, switching between browser back and forth, session may catch up, kill your current process and load text files from a previous session. Had to disable session restore.

Resources are not being hogged. Maybe 2GB of memory used out of 7 available. And CPU is barely doing anything. Hard disk is barely filled.

I’m ashamed to admit it, but I think maybe I was accidentally switching to a different desktop and opening Kate, and then switching to another desktop and opening another instance of Kate and opening same files. And maybe when session restore happened, once it loaded it switched me to a second desktop and I didn’t notice. Though I disabled 3 finger swipe, maybe when things get crowded windows somehow automatically rearrange.
So I’ll be investigating this further.

On Firefox freezing. I changed one option in about:config shortly after the Tumbleweed install, and now I reverted it back, switched **"**browser.tabs.unloadOnLowMemory" from false back to true, and it seems like Firefox stopped freezing. Fingers crossed.