The common function of IMAP is
Mark As Flaged/Unflaged
isn't in SuiteCRM 7.9 mail system yet. (in older version 7.8.x was and was very usefull)

User will available to mark the emails as flaged/unflaged
Hi @Mausino Mark as Flagged/Unflaged has already been raised here: #3616 as a high priority issue. Please edit the title to "Mark As Read/unread" or update the other PR and close this one. Thanks.
@Dillon-Brown i know.. but @daniel-samson did the patch only for Relate to, Reply To All and Forward functions.
There is nothing about Read/Unread function and flag function is not explained good.
Do you want that i close this ticket or i will rewrite the old one that i remove the text about flag part ?
@Mausino It's better to have the issues as separated as possible instead of having them all in a single issue.
I would remove the "Flaged/Unflaged" from the other issue and keep it here. Or alternatively you could separate them further and make a new issue for "Mark As Read" and make this one just for "Mark As Flaged/Unflaged".
@Dillon-Brown ok... I will do this as you wroted :)
PR: #3648