Unable to set user as PR reviewer when multi-byte chars are set in the full name of Atlassian account

Steps to reproduce:

1. Access https://id.atlassian.com and set your full name as “山田” or other multi-byte names
2. In the repo that the user has access to, create a new PR and mention that user as PR reviewer by entering “山田”

Expected Result:

The user appears in the suggested list

Actual result:

The user doesn't show up

Workaround:

Change the full name to a single-byte one from https://id.atlassian.com