This has nothing to do with thunderbird's imap CONDSTORE. However, the searchfox "blame" link in for bug "support IMAP RFC 4551 - CondStore extension", bug 436151 links to this report due to a commit typo mentioned here: bug 436151 comment 20.
Bug 336151 Comment 2 Edit History
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This has nothing to do with thunderbird's imap CONDSTORE. However, the searchfox "blame" link for bug "support IMAP RFC 4551 - CondStore extension", bug 436151 links to this report due to a commit typo mentioned here: bug 436151 comment 20.