iOS: copy/paste context menu not working on modal fields

Description:

On iOS (no matter if Safari or Chrome) it is not possible to copy/paste from/into modal fields like for example the login form or when entering 2FA authorization codes. That might seem irrelevant for because there is a native iOS App, but the whole /admin/ interface is still rendered in the built-in browser, which has the same issue. Seems like a race condition, because the iOS context menu shortly shows up, and by tapping repeatedly you might be lucky and get the context menu.

Steps to reproduce:

1. Open the rocket chat login page in Safari or Chrome
2. Try to tap into the username or password field to open the copy/paste context menu

Expected behavior:

After tapping the modal field, the context menu should show up for copy/paste text.

Actual behavior:

The context menu only shortly pops up very shortly (very small) or not at all.

Server Setup Information:

• Version of Rocket.Chat Server: 5.4.3
• Operating System: Ubuntu
• Deployment Method: snap
• Number of Running Instances: 1
• DB Replicaset Oplog: rs0
• NodeJS Version: v14.19.3
• MongoDB Version: 4.4.15 / wiredTiger (oplog Enabled)

Client Setup Information

• Desktop App or Browser Version: current Safari or Chrome
• Operating System: iOS

No source file or test is named. First reproduce the login or 2FA modal field behavior in Safari and Chrome on iOS, then trace the modal and text-field handling used by that page. Done means copy and paste context menus remain available after tapping modal fields, including in the /admin/ interface.