Clicking specific Chrome extension buttons

That may have been in this comment:

Based on that, I discovered that the extension that I am trying to automate could indeed have a shortcut set. Here's what I did:

  1. Click on the Extensions icon,
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    That opened a dropdown menu.
  2. Click on Manage Extensions:
    image
    That opened the page chrome://extensions/. You could go there directly, I presume.
  3. Click on Keyboard Shortcuts:
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    That opens a list of extensions.
  4. Find my extension in the list and click the pencil/Edit icon:
    image
  5. Type my shortcut key combination, which appears to have to be a letter with an opional Shift and at most one of ⌘, ⌃, ⌥.
    image