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The Dropbox website works quite nicely on Real Opera™.
As an aside, Dropbox is hiring a privacy-hating war criminal: http://www.drop-dropbox.com/
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I don't use Opium or Chromium, but I also began getting lots of error messages this week in Otter - when logging to Vivaldi, visiting some https addresses, etc. The other webkit browser I use is Luakit which gives no error messages.
Luakit may be too chill though. There's an Estonian webmail site where I occasionally log in, and every browser always gave an invalid certificate warning there for two decades already - except Luakit (and IE, I suppose the website was originally designed with IE in mind).
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Opium just started to suck a little bit more. It is supposed to communicate directly with the webserver, using plain TCP provided by the OS. That is the whole reason why I have an alternate browser on my system. So that it functioned completely independently from Microsoft.
It's something similar with the proxy server(s), btw.
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