Black Box Outline around Buttons (NOT an Accessibility Option)

In various apps, whether it be YouTube or Settings, or any other apps, a button is randomly outlined in a thin black line and it is driving me nuts as I cannot find the option for it. I am on iPadOS 14.4.2 (iPad Air 2) and I've carefully combed through every accessibility option to no avail.

VoiceOver is off

Zoom is Off

Magnifier is Off

Display Text Size >

Bold Text Off

Larger Text Off

Button Shapes off

On/Off Labels off

Reduce Transparency Off

Increase Contrast Off

Differentiate Without Color Off

Smart Invert Off

Classic Invert

Color Filters Off

Reduce White Point Off

Auto-Brightness Off

Audio Descriptions Off

Touch>

Assistive Touch (everything is Off or selected None)

Touch Accommodations Off

Shake to Undo Off

Switch Control Off

Voice Control Off

Sound Recognition Off

RTT Off

Guided Access Off

Accessibility Shortcut Off

These are the settings that I've combed through to ensure everything is off (among others) and I can't still find the source of these random black boxes...

Please see the images below

Here we can see that in the YouTube app, "General" button is randomly outlined in a box, and after taking a screenshot, we see in the second image that the "Done" button (in the upper left corner) is also randomly outlined