1759411 - Attachments with extensions that are not registered in the MIME type will need to be specified as an application to be opened every time with Thunderbird Ver91.7.0.

Status: UNCONFIRMED

(Thunderbird :: Message Compose Window, defect)

Description

[SUPERJET]

Attachment: DialogCompare.jpg

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/99.0.4844.51 Safari/537.36

Steps to reproduce:

I can reproduce by following these steps:

1. Start Thunderbird (Ver91.7.0) and click [Write]
2. Attach and [save] the attachment (.cab)
3. Double-click the attachment (.cab) saved from the draft

Actual results:

Ver91.7.0
which is: application/octet-stream
Do this automatically for files like this from now on. : Checkbox is not displayed
Focused on Save File every time, It is necessary to specify the application to be executed every time

Expected results:

Ver91.4.1
which is: Cabinet File
Do this automatically for files like this from now on. : Checkbox is displayed
If you enable the check box, specify the application and OK, it will open in the specified application by double-clicking.

Comment 1

[SUPERJET]

There is no problem with the extension registered as a MIME type.
example: .zip .pdf .xlsx .bmp .txt

Is it the effect that all attachment types with extensions that are not registered in the MIME type become application / octet-stream?
You cannot specify the application to open after that.

When I added the following registry, a dialog like that of Ver91.4.0 was displayed.

Example:
HKEY_CLASSES_ROOT \ .cab
Content Type
REG_SZ
application / Cabinet File

Comment 2

[SUPERJET]

sorry
I wrote Ver91.4.1 in the expected result
As shown in the image, Ver91.4.0 is correct.