Fault after upgrade to 3.3.8

 {{ [size=115]color=#368AD2[b]Support Request Template[/b][/color][/size]}}
color=#cc6600[b]What version of phpBB are you using?[/b][/color] phpBB 3.3.8
color=#cc6600[b]What is your board's URL?[/b][/color] www.motessparet.se
color=#cc6600[b]Who do you host your board with?[/b][/color] Loopia (Sweden), PHP=8.1
color=#cc6600[b]How did you install your board?[/b][/color] I used the download package from phpBB.com
color=#cc6600[b]What is the most recent action performed on your board?[/b][/color] Update from a previous version of phpBB3
color=#cc6600[b]Is registration required to reproduce this issue?[/b][/color] No
color=#cc6600[b]Do you have any MODs installed?[/b][/color] No
color=#cc6600[b]Do you have any extensions installed?[/b][/color] No
color=#cc6600[b]What version of phpBB3 did you update from?[/b][/color] phpBB 3.3.0
color=#cc6600[b]What styles do you currently have installed?[/b][/color] we_universal
color=#cc6600[b]What language(s) is your board currently using?[/b][/color] swedish
color=#cc6600[b]Which database type/version are you using?[/b][/color] MariaDB
color=#cc6600[b]What is your level of experience?[/b][/color] Comfortable with PHP and phpBB
{{color=#cc6600[b]What
actions did you take (updating your board; installing a MOD, style or
extension; etc.) prior to this problem becoming noticeable?[/b][/color]
Moving from 3.3.0 to 3.3.8, downloaded the first part, got an issue
and had to download an update_archive. After cleaning cache the forum is
running in 3.3.8 and under PHP 8.1.}}
{{color=#cc6600[b]Please
describe your problem.[/b][/color] The page search for user/group and
hitting Search gives an empty page as a result, showing the source code
only gives "1" indicating an PHP-error in code. I've a PDF with screen
dumps showing this fault.}}
{{[size=60]Generated by SRT Generator[/size] }}