When this element was opened it ran functions generating extra activity that could cause a long task even on a relatively powerful device

• An INP below or at 200 milliseconds means that your page has good responsiveness.
• An INP above 200 milliseconds and below or at 500 milliseconds means that your page's responsiveness needs improvement.
• An INP above 500 milliseconds means that your page has poor responsiveness..

What is going on here? Let's take a look in the code and performance tab

INP is calculated by the longest of the interactions in the current lifecycle of the page, essentially its slowest reaction