Perhaps try restarting with add-ons disabled from the help menu. I have no issues, so I would guess it is an add-on, perhaps one injected into Thunderbird by an anti virus, instead of installed in a civilized manner. They have a tendency to mess up after every update.

Thanks for the suggestion, but it didn't work. I have few add-ons: enigmail and lightening. After disabling both and restarting, F5 and shift-F5 still have no effect.

ldaddario said

After disabling both and restarting, F5 and shift-F5 still have no effect.

I did not say do that. I said

Perhaps try restarting with add-ons disabled from the help menu.

Funny thing happens when you follow instructions. In my case you enter safe mode which resets a whole collection of things, some permanently if you select that. Your way just disabled the two add-ons. Do you have an anti virus that injects an add-on into a running instance of Thunderbird? They exist and their hacking fails when safe mode is used. Could you have a dud theme. They exist as well. Use safe mode and then tell me it did not work.

Matt said Use safe mode and then tell me it did not work. </blockquote>

Matt,

I used safe mode and I'm telling you it did not work. F5 and shift-F5 still have no effect.

Funny things happen when instructions are ambiguous and leave out the key point ("safe mode"), emphazing instead a side issue ("disable add-ons").

--Larry

I said. restart with add-ons disabled from the help menu. Nothing even vaguely ambiguous about that. Except for those that have issues following instructions.

I am using Thunderbird 60.7 on windows 10 and those features work for me. Perhaps your keyboard is broken, or has been reprogrammed for those function keys.

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