I'm not aware of an alternative for 68, but there are efforts to update the add-on:

https://github.com/wangvisual/expression-search/issues/87

If you right-click the sender's email in the Header Pane, Copy email address, then paste it in the Quick Filter Bar (Ctrl+Shift+K) and click the Sender button, you will see messages from that sender in the current folder.

Thank you. I'm now really having problems with TB. The new 68.5 wouldn't update on my system, got a msg to d/l and reinstall, now all of my old material and carefully constructed organization is gone. Waiting to hear back from my tech person about going back to previous setup via Windows, if that is even still possible in W10. I really have a problem when software rips the rug out from under me, it takes so much for me to get things the way I need them.

You very likely haven't lost your data, just that the update has caused TB to lose track of the profile folder. One simple step that often corrects this is to close TB, open the profile folder:

C:\Users\user\AppData\Roaming\Thunderbird\Profiles\8charstring.default (AppData is hidden by default)

and delete global-messages-db.sqlite

Next, launch Profile Manager: Windowskey+R, type thunderbird.exe -p

and select default in the list and see if TB launches with your data.

Thank you. When I got to the Profiles folder, there were 2 different folders that seem similar: 8characterstring.default and 8characterstring.default-release

The first has an earlier time stamp than the second. Just want to make sure I'm deleting from the correct folder.

Thank you!

I would not delete any folders until you get it sorted. but the default folder will be the one you want to use, and the one you want to remove your global-messages-db.sqlite from.

Note global-messages-db.sqlite is a search folder and when you delete it is is recreated when Thunderbird starts again. This may well make Thunderbird sluggish for some time (hours in some cases)

You could also use about:profiles to manage your profiles. This is a new feature that arrived with Version 68. https://thunderbirdtweaks.blogspot.com/2019/09/i-lost-my-profilemail-on-update-to.html

Excellent! I used the about:profiles explanatory link you sent me. It totally worked. I only had to get this far:

"If you have more than the current default profile listed, it is worth noting the name of the current default and clicking the "Launch profile in a new browser" button for other profiles shown. The label is incorrect and awaits correction. But clicking the button will launch Thunderbird in a new window with the selected profile loaded. If it happens to be what you are looking for. Click the Set as default button and you good to restart."

I needed to close the "bare, wrong-profile" version of TB and simply start using the "restored profile" version and all seems to be well. All my organization, folders, etc. are back-- I closed and reopened the "good" one just to make sure. AND, it opened much much faster than it was previous to the upgrade, so that's cool.

THANK YOU SO MUCH! phew. Even though TB mystifies me from time to time, the support I have found here has always come to the rescue. If Mozilla isn't funding TB anymore, will the support forum continue to be on the Mozilla site? If it is to move, can the archived material, usernames, etc move with it? Again, thank you. Oh, also, I did kick in a donation for TB and can do more in the future.

Victoria-nola said

THANK YOU SO MUCH! phew. Even though TB mystifies me from time to time, the support I have found here has always come to the rescue. If Mozilla isn't funding TB anymore, will the support forum continue to be on the Mozilla site? If it is to move, can the archived material, usernames, etc move with it? Again, thank you. Oh, also, I did kick in a donation for TB and can do more in the future.

Thanks for donation!

Thunderbird operates independently, but does use some of Mozilla's services. Support forum is one of them.

Thanks for this information about the forums.