Separate Security Issue, please update your Flash 27.0 r0 by removing it with this tool : https://helpx.adobe.com/flash-player/kb/uninstall-flash-player-windows.html Reinstall if use it with Flash Player Version: 30.0.0.134 Current Version https://get.adobe.com/flashplayer/otherversions/ Step 1: Select Operating System Step 2: Select A Version (Firefox, . . . .) Note: Other software is offered in the download. <Windows Only>

Try : press F7 if are in Caret Browsing Mode

I unistalled Adobe Flash Player, re-opened Firefox, opened my webmail app, and tried it again, with the exact same results.

Try a Clean Install : uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files , C:\Program Files(x86) & C:\ProgramData Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do :

• https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles
• https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer

Reinstall with Current Release Firefox 61.0.1 with a Full Version Installer

• https://www.mozilla.org/firefox/all/

Please let us know if this solved your issue or if need further assistance.

I followed the step-by-step instructions as suggested and it still does the exact same thing as before.

This only happens using Firefox and in my godaddy webmail only when I click in the Subject field before entering an address 1st, and only in Firefox with my godaddy webmail. In Chrome, it works fine, and in Firefox, my yahoo and gmail also work fine.