Have you searched GitHub? I have seen this PHP Notice in PDF’s before, I am not sure if there is an issue for it yet :huh:
Maybe the notice is associated with the delay, but that would be strange. There’s no reason to think a PHP notice could cause such a delay.
Maybe one of you can try increasing log levels to DEBUG and then run this while trying the PDF generation:
tail -f suitecrm.logYou will see a live log of what is happening, and you can hit return a few times to leave blank lines. If you notice any human-discernable delays, hit return to mark the place, and then go back to it to see what was happening.