Warning Theme AccessPress Parallax: trying to access array offset…..

After changing php version 7.6 to 8.1 I got the following warning:
warning: trying to access array offset on value of type bool in /home/.sites/478/site7163766/web/wp-content/themes/accesspress-parallax/inc/accesspress-functions.php on line 78
I am using WordPress 6.0.2 and the Theme accessPress Parllax Version 4.1
Can anybody tell me what to change in the accesspress-function.php that the warning will disappeare?
Thanks for your help!

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