Just to clarify - Firefox itself does not freeze, the uploading image is stuck in uploading state and never uploads, so it's a freeze on trying to upload and post comment in the Thunderbird Support Forum.
Bug 1773653 Comment 5 Edit History
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Just to clarify - Firefox itself does not freeze, the uploading image is stuck in uploading state and never uploads, so it's a freeze on trying to upload and post comment in the Thunderbird Support Forum. I'll move this to support.