@mention full name autocomplete doesn't work with international characters

codinghorror (Jeff Atwood) 10 يونيو 2015، 7:00م 17

Ok, reverting this for now, then.

الموضوع		الردود	مرات العرض
User mention full name search is not working for Unicode names Bug	5	1848	17 ديسمبر 2016
Username autocompletion not working with special characters? Bug	18	1723	2 يونيو 2022
Username completition broken for names with accents like Régis Bug	8	1679	22 أغسطس 2018
Dismissing autocomplete of username Feature	19	2565	10 فبراير 2016
Tab-completion should automatically add a space after a username UX pr-welcome	10	2980	1 مايو 2017