Creation of average load time segments

Good day,
how to filter the average page load time > 5 seconds in Matomo as a segment? Unfortunately I did not find this segment among the subitems. Is it possible to add it?
The goal is to find the average page load time >5 seconds or even > 4 seconds

The KPI is tracked in some widgets yet e.g. pages but its not possible to bring it out by segmentation.

@matthieu, is this something you could answer?
Thanks in advance.

Best regards