Can't scroll in Gmail address box using Firefox

[learninmypc]

I go into my gmail addy, click contacts, I get the choice of all or some,I click all & it brings up my contact list & click to add those I'm sending to & it adds them to the TO field so I then TRY to click the scroll down arrow but the cursor turns into a / & it will NOT scroll.
The up scroll works fine,not the down one. I have to left click in the TO field & use the arrow keys to get to the bottom so I can copy them to put them in the BCC field.
I just tried in Firefox safe mode,but still nothing.
Not sure exactly when it started because I use SeaMonkey mostly, but if anybody has any ideas,fine. I tried to do a screenshot of it, but the cursor isn't visible . TIA

 

[learninmypc]

I go into my gmail addy, click contacts, I get the choice of all or some,I click all & it brings up my contact list & click to add those I'm sending to & it adds them to the TO field so I then TRY to click the scroll down arrow but the cursor turns into a / & it will NOT scroll.
The up scroll works fine,not the down one. I have to left click in the TO field & use the arrow keys to get to the bottom so I can copy them to put them in the BCC field.
I just tried in Firefox safe mode,but still nothing.
Not sure exactly when it started because I use SeaMonkey mostly, but if anybody has any ideas,fine. I tried to do a screenshot of it, but the cursor isn't visible . TIA

Disregard this thread because I tried same thing on another pc (NOT mine) & it happened on it too. Thanks for the views. Have a great day.

Ok, I'm hoping to revive this thread because when I updated SeaMonkey the other day, it started doing the same thing.
Any ideas on how to fix it??

 

[learninmypc]

Bumping for help