I'm not aware that is possible to set in the application. And if it can't be done in Firefox, then it can't be done in TB.

FWIW, I'm not finding any reports or requests for this in bugzilla.

OS settings

Well. I wonder what to do. Take a look at the difference in the uploaded photos. When I move the cursor into Thunderbird it becomes tiny. In Firefox the cursor is slightly larger than on the desktop; it is much larger than in Thunderbird. I wonder why.

The mouse pointer may be customized in Windows to do what you are wanting. It is not a Thunderbird function

Not Windows. :) LXQt is a desktop environment in a linux environment - in this case the user is Lubuntu.

I'm asking some linux people why this might happen.

Geoffrey are you using a HiDPi monitor (screen resolution larger than 1920x1080)? If yes, you might need to tweak some GTK parameters since Thunderbird uses it to draw the UI. You can have a look at https://wiki.archlinux.org/title/HiDPI#GDK_3_(GTK_3) for a reference. You can temporarily test it by starting Thunderbird from a terminal (e.g. `GDK_SCALE=2 GDK_DPI_SCALE=0.5 thunderbird`).

I have an external monitor (1680 x 1050) connected to my laptop (1920x1080). Using your code to launch from terminal gives me larger font and object scale - except for the cursor. Thanks for the suggestion though.

I did find this info - worth a try. https://www.reddit.com/r/Lubuntu/comments/33rfjj/simplest_way_to_change_the_cursor_size/

To change the size of your mouse cursor, go to:

• /home/USERNAME/.config/lxsession/LXDE/desktop.conf

find this line and change the value eg: to use 18 or 22 or whatever works for you. User at link used 48.

• iGtk/CursorThemeSize=18

Thanks for the direction @Toad-Hall. In

/home/[User Name]/.config/lxqt/session.conf   

, I found:

============================================

[General] __userfile__=true leave_confirmation=true lock_screen_before_power_actions=false window_manager=openbox

[Environment] BROWSER=firefox GTK_CSD=0 GTK_OVERLAY_SCROLLING=0 SAL_USE_VCLPLUGIN=qt5 SAL_VCL_QT5_USE_CAIRO=true TERM=qterminal XCURSOR_SIZE=60

[Font] antialias=true dpi=96 hinting=true

[Keyboard] beep=true delay=500 interval=30 layout="us,th" model=pc105 numlock=true options=grp:alt_shift_toggle variant=",tis"

[Mouse] acc_factor=20 acc_threshold=10 accel_factor=20 accel_threshold=10 cursor_size=60 cursor_theme=breeze_cursors left_handed=false

============================================

I couldn't open it in Notepadqq so I used LibreOffice Writer. To actually edit it I guess I'd use Vim. I don't think that it would only enlarge the Thunderbird cursor. I wonder if there is a GTK parameter just for the cursor and a way to apply it to Thunderbird. Perhaps @Danny Colin is on to something.