I think it's happened most often with IceCat but pretty much every browser I've tried has done this.
I'm not sure the cause but my Wi-Fi card drops the connection, /really/ often; it sucks but it's what I've got. The consequence is that I've noticed a particular behavior relatively frequently: when the connection drops, the browser I'm using will get stuck thinking that it cannot connect to the internet once the internet connection comes back, sometimes (especially if I tried to load a page while the internet connection was down). Trying to load any other page results in the "Unable to Connect" (or equivalent) page. I've tried IceCat, Ungoogled Chromium, Qutebrowser, Luakit, and Nyxt and had the same experience, in some capacity, with all of them. Loading a local HTML file works fine, during these spells, and I either have to wait a variable length of time before the spell passes or restart the browser. It doesn't seem to be something which impacts all browsers, at the same time: opening a new browser after one gets affected works fine or trying to use one of the other browsers I had open (especially if I hadn't been using this other browser while the internet connection had dropped).
