Attach method different behaviour from version 0.9.1 to 0.10.0

[fan-droide]

Error: 'list' object has no attribute 'items'

When I started running Flask-Mail version 0.10.0 I encountered the aforementioned issue, so I had to change the following line code:

 msg.attach("image.jpg", "image/jpeg", fp.read(), headers=[('Content-ID', '<image1>')])

To this:

msg.attach("image.jpg", "image/jpeg", fp.read(), headers={"Content-ID": "<image1>"})

Previously I was using Flask-Mail 0.9.1 but I found that with that version the parameter (headers={"Content-ID": "<image1>"}) does not work either and throws the error

Error: too many values to unpack (expected 2)

It should not throw any of the above mentioned errors

Environment:

• Python version: 3.9.6
• Flask-Mail version: 0.10.0 / 0.9.1
• Flask version: 3.1.0

[ThiefMaster]

0.9 to 0.10 can contain breaking changes even when following semver. and to me the new way looks clearly better.

it should, however, be added to the changelog, unless the old option w/ the list was undocumented and never expected to be a valid alternative