Channel Form errors in PHP 8.1

[mcfarlandonline]

EE Version 6.4.5
PHP 8.1

• MSM * Site

I have a front-end channel form showing this list of errors now that I've bumped them into PHP 8.1:

Deprecated
strpos(): Passing null to parameter #1 ($haystack) of type string is deprecated
ee/ExpressionEngine/Addons/channel/libraries/channel_form/Channel_form_lib.php, line 767

Severity: E_DEPRECATED
Deprecated
strpos(): Passing null to parameter #1 ($haystack) of type string is deprecated
ee/ExpressionEngine/Addons/channel/libraries/channel_form/Channel_form_lib.php, line 770

Severity: E_DEPRECATED
Warning
Cannot modify header information - headers already sent by (output started at ee/legacy/core/Exceptions.php:120)
ee/ExpressionEngine/Boot/boot.common.php, line 477

Severity: E_WARNING

Any insight on what needs tweaking here?

[intoeetive]

@mcfarlandonline what are the field (fieldtypes) that you are including into this form?

[mcfarlandonline]

@intoeetive,

• rich text editor
• text input
• select dropdown
• email address
• file
• radio buttons
• number input
• checkboxes

I'm also displaying logged-in members' avatars using the {exp:member:custom_profile_data} tags.