Jason

So, to make sure I’m understanding, it sounds likely to be the W3 Total Cache known bug that’s causing this issue? If this is a known bug, is there a known workaround?

On 2 – will look into that.

on 3 – The issue is there are page-specific unloads that I’m able to do in Asset Cleanup which Autoptimizer doesn’t seem to enable. I’ve turned off all other settings in Asset Cleanup though so that shouldn’t be an issue; I’m basically only using it for page-specific unloads.

Browser console definitely has errors; the warnings below are there even when the site works fine but enabling html optimization adds all the errors in the below. Pastebin of html at https://pastebin.com/6ppEmEX6.

DevTools failed to parse SourceMap: chrome-extension://gighmmpiobklfepjocnamgkkbiglidom/include.preload.js.map
(index):72 Uncaught ReferenceError: jQuery is not defined
    at (index):72
(index):84 Uncaught ReferenceError: jQuery is not defined
    at (index):84
(anonymous)	@	(index):84
(index):91 Asset CleanUp: "LIVE MODE" (test mode is not enabled, thus, all the plugin changes are visible for everyone: you, the logged-in administrator and the regular visitors)
notes-common-v2.js?ver=8.4.2-202017:158 Uncaught ReferenceError: jQuery is not defined
    at notes-common-v2.js?ver=8.4.2-202017:158
admin-bar-v2.js?ver=8.4.2-202017:2 Uncaught ReferenceError: _ is not defined
    at admin-bar-v2.js?ver=8.4.2-202017:2
autoptimize_8a97e797…eacee51b58d9a5.js:2 Uncaught ReferenceError: jQuery is not defined
    at autoptimize_8a97e797…eacee51b58d9a5.js:2
admin-bar.min.js?ver=5.4:2 Uncaught TypeError: f.hoverintent is not a function
    at HTMLDocument.<anonymous> (admin-bar.min.js?ver=5.4:2)
(index):1 A cookie associated with a cross-site resource at http://wordpress.com/ was set without the <code>SameSite</code> attribute. A future release of Chrome will only deliver cookies with cross-site requests if they are set with <code>SameSite=None</code> and <code>Secure</code>. You can review cookies in developer tools under Application>Storage>Cookies and see more details at https://www.chromestatus.com/feature/5088147346030592 and https://www.chromestatus.com/feature/5633521622188032.
(index):1 A cookie associated with a cross-site resource at https://wordpress.com/ was set without the <code>SameSite</code> attribute. A future release of Chrome will only deliver cookies with cross-site requests if they are set with <code>SameSite=None</code> and <code>Secure</code>. You can review cookies in developer tools under Application>Storage>Cookies and see more details at https://www.chromestatus.com/feature/5088147346030592 and https://www.chromestatus.com/feature/5633521622188032.
DevTools failed to parse SourceMap: chrome-extension://gighmmpiobklfepjocnamgkkbiglidom/include.postload.js.map
??-eJzTLy/QzcxLzilNS…xqZmZqXEWALkfL7E=:8 JQMIGRATE: Migrate is installed, version 1.4.1
DevTools failed to parse SourceMap: chrome-extension://gighmmpiobklfepjocnamgkkbiglidom/include.preload.js.map
(index):164 Uncaught ReferenceError: jQuery is not defined
    at (index):164
DevTools failed to parse SourceMap: chrome-extension://gighmmpiobklfepjocnamgkkbiglidom/include.postload.js.map

I tried to paste the image into that site in three different browsers and with two different file types using both the drag and drop approach, copy/paste, and file upload; none of them worked.

I’ve described how to recreate the issue exactly though, have you tried to do so? I’d really love to help you debug but at this point I don’t think I’m going to invest more time in doing so. I’d love it if you find and fix this, I’d prefer your plugin, but in the meantime I’ve found another that works and will be using it.