Summary

'Assigned to me' filter in the JIRA core boards isn't working as expected for the user names in brackets - e.g. User name: Charlie (Atlassian)
It also doesn't work when the user have uppercased letters in the username.

Steps to Reproduce

1. Create a new user with brackets in the username as below

Full name	Username	Email Address
Charlie Atlassian	Charlie (Atlassian)	abc@aaa.com

2. Create a business project
3. Create new task in the business project and assign it to the new user (created in step 1)
4. Login as the new user, and go to the business project board
5. Click on ' Find Issues' search button at the top-right in the board
6. Click on 'Assigned to me' filter

Expected Results

User should be able to see all the tasks assigned to him/her in the board.

Actual Results

User is not be able to see the new task assigned to him/her.

Notes

Issue still persists ever after removing the brackets in the user name. i.e., changed the user name from 'Charlie (Atlassian) to 'Charlie.Atlassian' or 'Charlie Atlassian.

Workaround

There is no known workaround at the moment.