Pure os (plasma) Hangs Freeze issue

HI Everyone Hoping to see good.

I am using pureos Plasma and switched from Ubuntu 18.

I was researching for Free OS without any blob or any proprietary software and I came to know about Trisquel and PureOs I appreciate their efforts to build these OS.

While I am facing issues of freeze and hanging while using firefox and chormium or any applications it freezes & I need to restart system idk what is making it freeze can anyone let me know as I have

8GB Ram
500 GB Hard Drive

any help is highly appreciate.!!!