diff --git a/doc/bugs/multibyte_characters_broken.mdwn b/doc/bugs/multibyte_characters_broken.mdwn
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+### Please describe the problem.
+git annex add is not fully compatible with multibyte-characters in filenames and may generate filenames with invalid character sequences.
+
+### What steps will reproduce the problem?
+$ git init test; cd test
+$ git annex init test
+$ echo bla > 01-06\ 三石琴乃・富沢美智恵・久川綾・篠原恵美・深見梨加\ -\ Tuxedo\ Mirage.flac
+$ git annex add 01*
+
+The last command generates an invalid character sequence as filename which, depending on the filesystem, may cause an error:
+
+Example output:
+add "01-06 \344\270\211\347\237\263\347\220\264\344\271\203\343\203\273\345\257\214\346\262\242\347\276\216\346\231\272\346\201\265\343\203\273\344\271\205\345\267\235\347\266\276\343\203\273\347\257\240\345\216\237\346\201\265\347\276\216\343\203\273\346\267\261\350\246\213\346\242\250\345\212\240 - Tuxedo Mirage.flac"
+  .git/annex/othertmp/: openTempFile template ingest-01-06 三石琴乃・富沢美智恵・久川綾・篠原恵美・深見梨�: invalid argument (Invalid or incomplete multibyte or wide character)
+
+failed
+add: 1 failed
+
+
+### What version of git-annex are you using? On what operating system?
+git annex 10.20250630
+NixOS 25.11pre851350.3b9f00d7a7bf
+
+### Please provide any additional information below.
+
+Creation of the file fails due to zfs being set to only accept valid utf-8 filenames (utf8only=on, normalization=formD), which greatly helps me detecting encoding issues in filenames.
+The original file obviously has a correct encoding, but it seems that git annex generates a new filename by just cutting of the filename after a specific byte, instead of taking character lengths into account.
+
+### 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)
+I use git annex to manage my whole music collection successfully.