Remote content abruptly enabled for just one email message
I've encountered one message in Thunderbird that has remote content enabled (which I don't recall explicitly enabling). In Settings, under "Allow remote content in messages" (unchecked), the "Exceptions..." list is empty. I've also cleared the cache, switched to offline mode, and went back to that message, but it still shows remote content.
Wšykne wótegrona (3)
The first obvious question is how do you know the content is remote? Simply showing images for instance does not mean that they are coming from a remote location, they may be embedded in the body of the email.
It looks to not be embedded since there are direct links to images in the source code.
according to http://forums.mozillazine.org/viewtopic.php?p=11972243 the decision to allow images in a specific message is stored in the MSF database file for the folder, so if you repair that folder (Right click folder > Properties > repair) that should blow away that saved setting. I assume that is what you were trying to do with the clearing of the cache etc.
Musyśo se pla swójogo konta pśizjawiś, aby na pśinoski wótegronił. Pšosym stajśo pšašanje, jolic hyšći njamaśo wužywaŕske konto.