Hi team,
I’m reporting a critical performance issue involving the FullCalendar plugin on Bubble.
We identified a severe browser freeze on one of our production pages, and after investigating the behavior in detail, it appears that the calendar is repeatedly injecting duplicate <style> tags into the document <head> during renders/re-renders.
What is happening
The same CSS rule seems to be added over and over again:
.fc-timegrid-event-short { … }
Instead of being injected once, this style appears to be duplicated continuously, which causes the DOM to grow excessively and significantly degrades performance.
Important note
At this stage, I cannot say with full certainty whether the root cause is:
- the plugin itself,
- the way Bubble is re-rendering the plugin element,
- or a combination of both.
However, the issue becomes much more noticeable in production scenarios with a high volume of short appointments (especially 15-minute events), and in these cases the agenda performance is heavily impacted.
When the calendar contains many short events, the page becomes extremely slow and interactions such as opening a scheduling popup or navigating the calendar can take a long time. In practice, this makes the agenda difficult to use.
I’d like to understand:
- whether this is a known issue in the FullCalendar plugin wrapper for Bubble,
- whether there is any update or recommended configuration to prevent this repeated style injection,
- and whether there is any mitigation available for high-volume calendars with many short events.
If helpful, I can also share more details about the reproduction pattern and the behavior we observed in production.
Could you please investigate this?
Thank you.
