Cinnamon - Expo thumbnails for non active workspace does not update.

Describe the bug In Expo view only the currently active workspace thumbnail is updated / animated. Any inactive workspace thumbnails are 'frozen'

To Reproduce Open an application with a window that will show activity for sometime - e.g. a video in browser/xplayer or a terminal running find / *

Go to expo view, observe that the thumbnail for the active workspace shows the window updating in realtime. Switch to another workspace and immediately return to expo. Observe the original workspace thumbnail is frozen.

Expected behavior All workspace thumbnails should update in expo irrespective of which is the active workspace

Frequency Does the issue happen:

[x] Always
[ ] Randomly

Edition (Desktop environment): In which edition is this happening?

[x] Cinnamon Edition
[ ] MATE Edition
[ ] Xfce Edition

Live or post-install: Indicate if this is happening after the installation, or during the live session:

[x] Post-install
[x] Live session

Screenshots If applicable, add screenshots to help explain your problem.

Locale: Paste the output of locale.

steve@steve-HP-Pavilion-g6-Notebook-PC:~$ locale
LANG=en_GB.UTF-8
LANGUAGE=en_GB:en
LC_CTYPE="en_GB.UTF-8"
LC_NUMERIC="en_GB.UTF-8"
LC_TIME="en_GB.UTF-8"
LC_COLLATE="en_GB.UTF-8"
LC_MONETARY="en_GB.UTF-8"
LC_MESSAGES="en_GB.UTF-8"
LC_PAPER="en_GB.UTF-8"
LC_NAME="en_GB.UTF-8"
LC_ADDRESS="en_GB.UTF-8"
LC_TELEPHONE="en_GB.UTF-8"
LC_MEASUREMENT="en_GB.UTF-8"
LC_IDENTIFICATION="en_GB.UTF-8"
LC_ALL

Drivers: Paste the output of inxi -Gxx.

steve@steve-HP-Pavilion-g6-Notebook-PC:~$ inxi -Gxx
Graphics:
  Device-1: Intel 2nd Generation Core Processor Family Integrated Graphics 
  vendor: Hewlett-Packard driver: i915 v: kernel bus ID: 00:02.0 
  chip ID: 8086:0116 
  Display: x11 server: X.Org 1.19.6 driver: modesetting unloaded: fbdev,vesa 
  resolution: 1366x768~60Hz 
  OpenGL: renderer: Mesa DRI Intel Sandybridge Mobile v: 3.3 Mesa 19.0.2 
  compat-v: 3.0 direct render: Yes

Crash report:

''Stack trace'' If you are reporting a crash. Go to "Software Sources" and enable the debug symbols. Then go to "System Reports" and extract the stack trace for your crash and paste it here.

''Dmesg'' If you type dmesg in a terminal, you should see a line corresponding to the crash. Paste it here.

Additional context Add any other context about the problem here.

linuxmint / mint19.2-beta

Cinnamon - Expo thumbnails for non active workspace does not update. #65