Open Arknights on PC (screen sharing in the browser doesn't work on mobile)
Goto the operator page
Click "Start Capture" and select the arknights window
Slowly scroll trough your operators untill every operator is captured
The site should be able to process about 1-2 frames every second.
So as long as an operator is on screen for about a second it should get captured.
Click "Stop Capture"
Capture
or pick screenshots
Detected 0 operators
0 Detection errors
Having detection errors is often harmless, as usually the operator is properly detected in another frame