Crashes imply crash reports and Id's. With those someone can look up exactly what the crash is about. Please post yours. See https://support.mozilla.org/en-US/kb/mozilla-crash-reporter-tb#w_viewing-crash-reports

bp-d8e59c9e-5fc7-4e81-83c3-b8d270240728 7 minutes ago bp-dfe7cedb-4d58-40c7-a13d-9bf9c0240728 11 minutes ago bp-50d555a5-5b88-4ae5-a1b5-17bef0240728 18 minutes ago bp-b8eb6f21-9c76-4546-81e8-7fa1f0240728 20 minutes ago bp-d81cb2d1-73e6-408c-9259-e79520240728 21 minutes ago bp-c64b395b-6e5a-4e47-a2da-a1cc80240728 51 minutes ago bp-aeb2c4f7-966a-4a70-a7ed-ed0a70240728 6 hours ago bp-90671f87-f989-47ea-ac24-48cc50240727 23 hours ago

Additional crashes -- can someone help out?

bp-fb974574-3be7-4314-812b-f3bec0240731 1 minute ago bp-32dd68e3-b043-41f6-8701-485310240731 15 minutes ago bp-c7269736-d12f-41de-a299-d20fd0240731 2 hours ago bp-c6b21a3c-adc5-4c5b-bc7c-c785c0240731 3 hours ago bp-4c1683e9-eef2-418e-bbf9-dbc320240731 5 hours ago bp-6432b167-746d-4c46-8e40-e9dc20240731 8 hours ago bp-f5180084-387c-4d5b-8cf4-75a2b0240731 9 hours ago bp-be539908-e19a-4973-8dd4-f16b60240731 21 hours ago bp-fe61aebf-e114-4de8-afa6-6e6f00240730 1 day ago bp-7f96a43b-3d07-4831-b37c-106710240730 1 day ago

I have only had time to look at three of those crashes, but they are multiple issues in multiple code. One ting I notices is you are using bitdefender, and I am not and I am having no crashes.

You say you tried with it turned off, I suggest you try with windows in safe mode with networking. But not you will need a wired internet connection as WiFi does not work in Windows safe mode.

The other thing is the crashes appear to my small understanding to involve out of bounds issues so it may be we are talking about corrupted files. They are also extremely rare.

For instance https://crash-stats.mozilla.org/report/index/d8e59c9e-5fc7-4e81-83c3-b8d270240728#tab-details has only one occurrence. and https://crash-stats.mozilla.org/signature/?product=Thunderbird&signature=js%3A%3Agc%3A%3ATraceEdgeInternal has eight.

So I am going to suggest you try a scan of your hard disk storage with the Microsoft tool chkdsk https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/chkdsk?tabs=event-viewer It is possible that the actual files are not logically stored for some reason.

Another thing I noticed is some of the crashes involve MORK. As work has been ongoing for years to get MORK out of Thunderbird, about the only place it remains in common usage after the address books were converted to SQlite is in the folder index files (MSF files) that are used to populate the user interface list. These are basically a cache, although also used to store folder preferences like list headings and sort order. I would suggest you might want to rename or delete them, or some of them, and see if a corrupt file is the actual issue. Personally I would backup my profile folder all 50 something gig of it and just delete all the MSF files in the profile folder with Thunderbird closed down of course.