ProtonMail Bridge IMAP

Using the newly released ProtonMail Bridge I am unable to add an IMAP account, with the error:

“Sorry, this folder does not exist. (IMAP)”

Log contents:

----------IMAP----------

* OK [CAPABILITY IMAP4rev1 STARTTLS AUTH=PLAIN AUTH=LOGIN ID APPENDLIMIT] IMAP4rev1 Service Ready
1 STARTTLS
1 OK Begin TLS negotiation now
2 LOGIN "photosphere@protonmail.ch" *********
* CAPABILITY IMAP4rev1 AUTH=PLAIN AUTH=LOGIN ID XSTOP APPENDLIMIT
�2 OK [CAPABILITY IMAP4rev1 IDLE MOVE SPECIAL-USE ID XSTOP QUOTA APPENDLIMIT=26214400] LOGIN completed
3 LIST "" ""
* LIST (\Noselect) "/" "/"
3 OK LIST completed
4 ID NIL
* ID (support-url https://protonmail.com/support name ProtonMail vendor "Proton Technologies AG")
4 OK ID completed
ID (support-url https://protonmail.com/support name ProtonMail vendor "Proton Technologies AG")
����5 LIST "" "*"
�H�Y|�� 

The Bridge is required to provide a decryption mechanism for ProtonMail. I’ve followed the instructions that might apply to a Thunderbird account, found here:

Are there any related issues?

Question was originally asked in closed Issue #367, with another user experiencing the same issue.

What operating system are you using?

OSX 10.11.6

What version of Mailspring are you using?

Version 1.0.10 (1.0.10)

Bug?

Do you have any third-party plugins installed? If so, which ones?

None

Is the issue related to a specific email provider (Gmail, Exchange, etc.)?

ProtonMail Bridge

Feature Request?

Does this feature exist in another mail client or tool you use?

Might be a feature request, considering Mailspring seems to think that there aren’t any selectable folders in the account. The bridge appears to be connecting as expected, and the Thunderbird works as expected.


(Originally posted by stellarsquall on GitHub.)

NOTE: Extensive technical notes on the original issue.

Underway with:

Thanks @bl00mber!