Can't reply to any post when using firefox

Problem appeared suddenly. Can't reply to any post anymore. no normal replies not reply with qoute. nothing. All i get is the turning wheel which turns forever but nothing happens. I didn't change anything in firefox. I tried deactivating all add ons. tried restarting firefox, tried cleaning with ccleaner. nothing helps. tried with google chrome and it works. Can somebody give me a hint? thanks

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Update: Damn, didn't work for 2 hours and now after I post this it seems to work again. thread can be closed/deleted