Drag the following link to your Bookmarks bar to create a bookmarklet to change your cursor to 44×44 pixels square for testing WCAG Target Size and Pointer Target Spacing requirements (ref: Target Size and 2.5.5).
I forked Jared’s post and added a feature — you can press Esc and CSS gets added to set the cursor to revert. Obviously there is some risk to using Esc, but I figure for testing it is fine, until it is not, and then you can customize it to a key or combination that works for you. A better solution is to destroy the CSS block entirely, but I have to go make dinner.
Note your browser's Content Security Policy may prevent the script from modifying a page, in which case you can run it in the browser console. In Firefox use Ctrl + Shift + K, In Chrome use Ctrl + Shift + J.