Just a half-baked update: there is a CORS error in the console. L.E. filed this bug.
The application shell was using “security.fileuri.strict_origin_policy” to overcome that.
It might be that the http server needs to be upgraded to https. I tried that with a self-signed certificate but fought another bug:
// JavaScript error: file:///usr/lib64/mozembedlite/components/EmbedLiteErrorPageHandler.js, line 162: NS_ERROR_XPC_NOT_ENOUGH_ARGS: Not enough arguments [nsICertOverrideService.rememberValidityOverride]
overrideService.rememberValidityOverride(uri.asciiHost, uri.port, cert, flags,
temporary);
The number of arguments seems to have grown with an object between port and cert as in security/manager/pki/resources/content/exceptionDialog.js from gecko dev. Or I might be wrong cause I can’t get rid of the unsigned certificate screen.
(Quest continues)