Bug: TBird 78.3.1 under OS X 10.13.6: "hangs" while editing text in new email
Status: RESOLVED
Priority: --
Resolution: DUPLICATE
Created: 2020-09-29 15:56:07+00:00
Resolved: 2020-09-29 23:45:44+00:00

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:81.0) Gecko/20100101 Firefox/81.0

Steps to reproduce:

This bug report replaces bug 1667631 because it contains a better and more comprehensive description of the bug.

The problem appears to be limited to Mac OX X 10.13.6 with Thunderbird 78.3.1.
It can be demonstrated as follows:
 * click on Write icon to start a new email
 * enter a couple of lines of text
 * use double-click or click-drag to select a word
 * try typing in replacement text, or Delete, or Cut-Paste
 * after a small but variable number of such operations updating will "hang"
 * during a hang, which may occur with the selected text still highlighted or not, new text cannot be selected and the cursor cannot be positioned for text entry.
 * the "hang" can be cleared by using Save (cmd-S) or by clicking in the top part of the window.  However it will return again as new selections are made and manipulated.
 * in some cases when selecting a word and typing in replacement text the selected text will "flicker" back and forth between original and newly entered text at about a 1 Hz rate.
The problem does NOT occur if the computer has been booted into Safe Mode (i.e., restarted while Shift key is held)
While simply typing in an email works, any editing such as retyping or Cut/Paste is problematic to the point of being very frustrating.
 
Test environment
 Computer A: Mac mini i5 (2011)
   drive #1, SSD, bootable to 10.13.6 (17G14033), updated… 2020-005, daily use
   drive #2,  HD, bootable to 10.13.6, rarely booted or used
 Computer B: Mac mini i7 (2012)
  drive #1, SSD, bootable to 10.14.6 (18G6032), fully updated
  drive #2,  HD, bootable to 10.15.7 (19H2), fully updated

Test results:
Using Computer A
 booted to drive #1:
  removed all user account logins, background tasks, etc.
  downloaded & re-installed the current Thunderbird 78.3.1 (64 bit)
  Tbird 78.3.1 shows problem (unless booted into Safe Mode)
  Tbird 68.0 (64-bit)   is OK
  Tbird 52.9.1 (64-bit) is OK
 booted to drive #2 {as a control against corrupted System}
  Tbird 78.3.1 shows problem (unless booted into Safe Mode)

Using Computer B
 booted to drive #1 (OS X 10.14.6, Mojave)
  Tbird 78.3.1 is OK
 booted to drive #2 (OS X 10.15.7 Catalina)
  Tbird 78.3.1 is OK

I believe this series of tests demonstrates that Tbird 78.3.1 has a problem with text updating that is specific to Mac OS X 10.13.  The possibility of being due to corrupted System software or interference by other sotfware has been reasonably eliminated by replicating the problem when booted to Computer A's rarely used drive #2.

Additionally, the fact that booting to Safe Mode avoids the problem suggests that the faulty code is related to some module loaded only in normal (non-Safe) environments.

I should also mention that Tbird 78.3.1 on OS X 10.13.6 appears to have some updating / refresh issues when selecting multiple emails.  Though I have not carefully evaluated this issue, it can be seen by
 * opening the inbox
 * selecting multiple discontinuous emails using Cmd-click
 the selected emails will be highlighted, but occasionally an email will not highlight until the cursor is moved to the next one.

Cordially,
Garth Fletcher

 


Actual results:

see above


Expected results:

see above