Imagine.php Fatal Error When Upgrading From 4.3.5 To 4.3.6

Happy 4th of July to US members.
I attempted to upgrade my development site recently from 4.3.5 - 4.3.6. Have not made any changes or used the site since 2018.
I received the following famous message when logging into the client side "Service Unavailable", "Sorry, service is temporarily unavailable." (no problems in Administrator module)
The error is:
"PHP Fatal Error
Call to undefined method Imagick::setImageOpacity()
Error at
app/lib/vendor/imagine/imagine/lib/Imagine/Imagick/Imagine.php, line: 82"
Some facts:
1. uninstalled all third party add-ons before attempting to upgrade
2. Cleared cache from within the admin after upgrade. Did not delete any cache folders manually
3. PHP version: 5.6
4. PHP Extension imagick is enabled. gd is available and so is gmagick. These are not checked.
5. The dev site is in a subdirectory under the production site. Can't change PHP version of one without changing the other.
6. The production site on version 4.3.5 is functional in the admin and client end no changes made since 2017/2018.
7. I did search the forum and found this from 2019: There seems to be multiple potential fixes, but none definitive.
Would appreciate a solution, hopefully, not complicated.
Thank you,

Please update Imagick library on your server up to 7 version

eConLabs- thank you for your reply.

I did check the Imagick Library.

This is what is on the server (7.0.10): I will not be upgrading, but will be doing a fresh install. Thank you for looking-Bob10 Q16

			imagick module
			imagick module version
			imagick classes
			Imagick, ImagickDraw, ImagickPixel, ImagickPixelIterator, ImagickKernel
			Imagick compiled with ImageMagick version
			ImageMagick 7.0.10-10 Q16 x86_64 2020-07-16
			Imagick using ImageMagick library version
			ImageMagick 7.0.10-10 Q16 x86_64 2020-07-09

x86_64 2020-07-09 I a

As alternative, in the app/lib/vendor/imagine/imagine/lib/Imagine/Imagick/Imagine.php file replace



ErrorHandling::ignoring(E_DEPRECATED, function () use ($imagick, $pixel) {