diff --git a/doc/bugs/Missing_sanity_check_of_group_names._Special_group_names_should_not_be_allowed..mdwn b/doc/bugs/Missing_sanity_check_of_group_names._Special_group_names_should_not_be_allowed..mdwn
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+### Please describe the problem.
+
+As documented in [[git-annex-matching-options]], `--copies` accepts `trustlevel` or `groupname` in the following format:
+
+* `--copies=trustlevel:number`
+* `--copies=groupname:number`
+
+This is ambiguous in the unlikely case where a user might come up with the idea to create a group called `trusted`, `semitrusted` or `untrusted` (`remote.<name>.annex-trustlevel`). It should thereby not be allowed to use such special groups.
+
+### What steps will reproduce the problem?
+
+
+[[!format sh """
+## In an annex repo:
+
+git annex group here trusted
+
+## What does this command do now?
+## For reference, it interprets it as `--copies=trustlevel:number`
+git annex find --copies=trusted:1
+
+"""]]
+
+### What version of git-annex are you using? On what operating system?
+
+	git-annex version: 6.20180509
+	build flags: Assistant Webapp Pairing S3(multipartupload)(storageclasses) WebDAV Inotify DBus DesktopNotify ConcurrentOutput TorrentParser MagicMime Feeds Testsuite
+	dependency versions: aws-0.14.1 bloomfilter-2.0.1.0 cryptonite-0.20 DAV-1.3.1 feed-0.3.11.1 ghc-8.0.1 http-client-0.4.31.1 persistent-sqlite-2.6 torrent-10000.0.0 uuid-1.3.12 yesod-1.4.3
+	key/value backends: SHA256E SHA256 SHA512E SHA512 SHA224E SHA224 SHA384E SHA384 SHA3_256E SHA3_256 SHA3_512E SHA3_512 SHA3_224E SHA3_224 SHA3_384E SHA3_384 SKEIN256E SKEIN256 SKEIN512E SKEIN512 SHA1E SHA1 MD5E MD5 WORM URL
+	remote types: git gcrypt p2p S3 bup directory rsync web bittorrent webdav adb tahoe glacier ddar hook external
+	operating system: linux x86_64
+
+### Have you had any luck using git-annex before? (Sometimes we get tired of reading bug reports all day and a lil' positive end note does wonders)
+
+Yes! Thanks so much for your work!