I messed up in editing the manifest registry key, I can't actually reproduce either. Eynan, can you please test again, preferably with a new profile, and give more details about version of firefox or anything else that might be different with your setup?
Bug 1575162 Comment 9 Edit History
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I messed up in editing the manifest registry key, I can't actually reproduce either. Eynan, can you please test again, preferably with a new profile, and give more details about version of firefox or anything else that might be different with your setup ?