Now ProtonMail doesn't work

[Wish You Were Here]

I get an 'unsupported browser' page which has a link to a useless help page saying SM isn't good enough for them.

[DanRaisch]

Have you tried tweaking the User Agent String to see if they are basing that rejection on that?
See if this thread is helpful -- http://forums.mozillazine.org/viewtopic ... #p14894541

[Frank Lion]

I get an 'unsupported browser' page which has a link to a useless help page saying SM isn't good enough for them.

I don't.

Both new and old versions of Protonmail are working 'just fine' for me.

[Wish You Were Here]

Have you tried tweaking the User Agent String to see if they are basing that rejection on that?
See if this thread is helpful -- http://forums.mozillazine.org/viewtopic ... #p14894541

I turned off 'advertise for FF' in preferences and deleted the UA string I had. Still nothing.

[davidb_sk]

I don't seem to have any problems with Proton Mail, either. I haven't done anything to SeaMonkey apart from turning off Firefox Compatibility notifications.

[Wish You Were Here]

^^^ You just posted your email openly.

[davidb_sk]

I've blurred it now, for those concerned, but my email is the same as my forum User I.D. so I didn't feel it to be a big secret.

Anyway, what is your User Agent String set at, under the HTTP Networking heading? Is it set to "Identify as SeaMonkey"?

[ndebord]

I get an 'unsupported browser' page which has a link to a useless help page saying SM isn't good enough for them.

FWIW, I have no problems with Proton Mail.