inline background styles in squidguard package
When you look at squidguard's Target Category list (assuming it's populated), the text is too faint as compared to the light-grey cell colour.
It looks like the bootstrap classes haven't been applied. Some of the files with hard coded styles include:
#2 Updated by Kill Bill about 4 years ago
Anyone filling bugs about this package should consider a bounty to get it rewritten from scratch. I guess nothing short of $1K would get things started. Whatever still keeps working in this package is a huge miracle and reading the code gives people an instant headache, to put it mildly. (And most certainly, noone should code things when on gallons of Russian vodka.)
I don't think it's a good idea to bring this mess over to 2.4.