A user, alexaw, reported an issue where non-ASCII tags in personal messages (PMs) do not return a list of PMs when clicked under /u/username/messages/tags or /tags. The issue is due to the parameterization of tag names, which strips special characters from strings. techAPJ identified the problem and created a fix by removing the parameterization (PR: https://github.com/discourse/discourse/pull/9839). The fix was tested rigorously and merged, resolving the issue.
When a personal message is tagged with non-ASCII character tag, the non-ASCII tag can be displayed in the PM Inbox, Sent, Archive and PM Tags list.
However, when clicking the tag under /u/username/messages/tags or /tags, only ASCII tag will return a list of PMs. Clicking on a non-ASCII tag will show “No topics found”.
I am using non-ASCII (Japanese and Chinese) tags sitewide, and haven’t had any problem except in PM.
The issue here is that we are parameterizing the tag name here which strips special characters from strings. This also means that tags with emoji in name will show same behaviour.