Images not showing in new messages

[nedb]

Version: 60.9.0 (32-bit); Windows 10

Apologies if this topic already solved, but I have searched repeatedly online and have never found a solution; all 'suggestions' fail.

Problem:
Create a new message; somewhere in Body, insert a local image (Insert > Image; migrate to and select an image, check Attach this image, select or not Alternate text (changes nothing relative to problem); image shows up in Image Preview. Click OK. Image fails to show in message. If try to send message anyway, fails with error that image could not be attached. The fact that the image shows in Preview proves a location mistake not made and that Thunderbird found the image at that point.

This is absolutely new behaviour (that is, this always worked many months or over a year ago). How is one supposed to add an image into the Body of a message?

Ned

[DanRaisch]

Does the same thing occur if you launch the application in Mozilla Safe Mode? http://kb.mozillazine.org/Safe_mode

[nedb]

Yes, exactly same problem in Safe Mode.

Further testing:

Strangely (to me), behaviour different:

- if using same computer and the same image is stored on a server and inserted as html (<img src etc), it works

- if use a different computer with same configuration (same TB version and Windows), the direct image insert works

There must be something different about how Thunderbird is behaving on just my computer (relatively recently), but I have no idea why or how to elucidate the problem.