* re-applying patch from @Hocuri from #2458
* apply sandbox isolation patch from @WofWca
* wait for gc as suggested by @WofWca, @Simon-Laux and others
* Update res/raw/sandboxed_iframe_rtcpeerconnection_check.html
Co-authored-by: WofWca <wofwca@protonmail.com>
* Update res/raw/sandboxed_iframe_rtcpeerconnection_check.html
Co-authored-by: WofWca <wofwca@protonmail.com>
* improve progress bar, inspired by @Simon-Laux and @WofWca
* comment about the gist of setNetworkAvailable()
* unify url-loading; this cleans up things and makes adding CSP more straight-forward
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Co-authored-by: WofWca <wofwca@protonmail.com>