A red bar above the timeline and a “Rendering” window after pressing Enter
The Rendering window after pressing Enter and the red bar above caption clips in Premiere Pro – what they mean and whether you need them for export.
This is normal Premiere behaviour and not a plugin error.
The red bar
Animated captions are animated graphics. Premiere marks such parts with a red (or yellow) bar above the timeline – it means the preview is calculated on the fly and may stutter on a slower computer.
The “Rendering” window after Enter
Enter on the timeline is the shortcut for Sequence → Render In to Out. Premiere then renders the heavy parts into preview files so they play back smoothly. You can wait or click Cancel – you lose nothing.
Is it needed for export?
No. When exporting, Premiere renders everything again anyway. A preview render only helps with smooth playback on the timeline.