Greasy Fork

Very good plug-in, but after using it, I can't pause the video on bilibili

There may be similar bugs on other websites.

Is there any way to kill the rounded corners without causing bugs?

Strange, this is the first report that the style really breaks any real functionality. Are you really sure it is this particular one causing the troubles?

Could you please install this trimmed-down version: https://greasyfork.org/en/scripts/552542-basic-unround-everything-everywhere ; disable this "full" one, and tell me if it changes the outcome?

OP, are you still having troubles? Could you provide more details? Have you tried the simplified variation from the previous comment?

I've tried that "bilibili" thing, but couldn't reproduce what you described: I could pause and resume video just fine with the style enabled.

No, I'm using this plugin now. I think you'd better not reinvent the wheel. This plugin has fewer bugs Obliterate Curves

Ah, so you are using this "Obliterate Curves" extension (or Chrome/ium) and it works without problems for you? Then good for you :]

I didn't know this exists, so thanks for the heads up. Looking at its source, it is indeed as bare-bones as it gets, so there is really not much room for bugs :)
It will square some radio buttons, and unlike my style will let slip some rounded elements such as avatar outlines and some logos.

If you'd happen to occasionally re-try my style (*alone*, without other intervening styles and extensions), I would still truly appreciate more detailed bug report with instruction I could be able to replicate myself. So far you've mentioned that it "has [more] bug [than simpler extension]" but I failed to understand and replicate any.