Describe the bug

Latest maddy doesn't report the IMAP IDLE capability, rendering message pushing unavailable.

Steps to reproduce

• Deploy maddy v0.5.2 (3ae0704)
• Connect via IMAP (thunderbird 91.5.0-0.1 via export MOZ_LOG=IMAP:4 in this case)
• Observe reported IMAP capabilities

Log files

0. maddy instance
   [Parent 11216: IMAP]: I/IMAP 7f63b185f800:redacted:NA:CreateNewLineFromSocket: 45 OK [CAPABILITY IMAP4rev1 LITERAL+ SASL-IR CHILDREN UNSELECT MOVE APPENDLIMIT APPENDLIMIT CHILDREN I18NLEVEL=1 SORT THREAD=ORDEREDSUBJECT COMPRESS NAMESPACE] AUTHENTICATE completed

Other examples for reference:

1. generic provider A
   [Parent 11216: IMAP]: I/IMAP 7f63bdbea000:redacted:NA:CreateNewLineFromSocket: 93 OK [CAPABILITY IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE IDLE SORT SORT=DISPLAY THREAD=REFERENCES THREAD=REFS THREAD=ORDEREDSUBJECT MULTIAPPEND URL-PARTIAL CATENATE UNSELECT CHILDREN NAMESPACE UIDPLUS LIST-EXTENDED I18NLEVEL=1 CONDSTORE QRESYNC ESEARCH ESORT SEARCHRES WITHIN CONTEXT=SEARCH LIST-STATUS BINARY MOVE SPECIAL-USE QUOTA] Logged in

2. generic provider B
   [Parent 11216: IMAP]: I/IMAP 7f63b1877000:redacted:A:CreateNewLineFromSocket: * CAPABILITY IMAP4rev1 CHILDREN ENABLE ID IDLE LIST-EXTENDED LIST-STATUS LITERAL- MOVE NAMESPACE SASL-IR SORT SPECIAL-USE THREAD=ORDEREDSUBJECT UIDPLUS UNSELECT WITHIN APPENDLIMIT=29360128

3. generic provider C
   [Parent 11216: IMAP]: I/IMAP 7f63b1869800:redacted:NA:CreateNewLineFromSocket: 61 OK [CAPABILITY IMAP4rev1 SASL-IR LOGIN-REFERRALS ID ENABLE IDLE SORT SORT=DISPLAY THREAD=REFERENCES THREAD=REFS THREAD=ORDEREDSUBJECT MULTIAPPEND URL-PARTIAL CATENATE UNSELECT CHILDREN NAMESPACE UIDPLUS LIST-EXTENDED I18NLEVEL=1 CONDSTORE QRESYNC ESEARCH ESORT SEARCHRES WITHIN CONTEXT=SEARCH LIST-STATUS BINARY MOVE SNIPPET=FUZZY PREVIEW=FUZZY XLIST LITERAL+ NOTIFY SPECIAL-USE] Logged in

Configuration file

Default configuration except $(hostname) and $(primary_domain)

Environment information

• maddy 0.5.2 on Debian 11.2
• https://maddy.email/specifications/#extensions