Slow performance on Big Sur

[Paul Dupuis]

On 12/14/2020 2:04 PM, J. Landman Gay via use-livecode wrote:
> My client is running Big Sur and says that changing cards in a stack 
> causes a very slow, stuttering display. The background image appears 
> in chunks and text in the fields comes in as sequential pieces. The 
> order of the display varies, sometimes the text appears first, 
> sometimes the background image. The first few cards are fairly normal, 
> but as she pages through the stack it gets slower.
>
> I had her watch Activity Monitor and CPU usage goes up as she 
> navigates through cards. At first the display is fairly normal but 
> each successive card change increases CPU useage a little bit. She 
> stopped when usage got to about 50% when she said it was unusable. 
> This was in the IDE. She says the standalone is even slower.
>
> Has anyone seen this? On Mojave and Catalina everything is fine.
>

I had a weird display issue where a transition between two cards left 
with one card semi-transparent behind the new card. It was also slow. I 
have a visual effect dissolve between these two cards I removed the 
visual effect and changing between the cards was fast and clean.

Examine any visual effect transitions you may have between cards.