Edit: I appreciate the downvotes, as though answering this question with honesty is undesirable behavior. Keep up the good work /r/svwebdev!
"All my Lubuntu devices" makes it sound like you have a lot of devices, thus increasing the likelihood of being easy to reproduce. There might even already exist a bug report which you could contribute to.
And, again being frank, I don't care enough to bother with scouring that for one that seems related enough to add to it, and then again reproducing the problem and collecting the appropriate logs and etc. And if experience is any indicator it'll just languish in their bug database for months or years anyway. I've got shit to do man, so I'll just use a product that works, thanks. It is not my responsibility to fix yours.
And I only brought it up because someone mentioned how much "better" a product Firefox is and my experience differed.