This bug is weird, especially because as far as I can tell it only occurs on one website – pixiv.net.
When I try to download picture from pixiv.net, save file dialog appears normally, I pick my location, click “save”, dialog disappears and nothing more happens.
Just tried this on https://www.pixiv.net/member_illust.php?mode=medium&illust_id=69633389 but it’s the same with any artwork I tried to download from site.
Putting shield down doesn’t help.
I use Brave 0.23.39 , x64 Linux