I have been using Hookmark and the Arc Browser together for about a year with no issues. However, within the past 2-3 weeks, I have discovered some problems. As I invoke Hookmark on pages in Arc that have been previously hooked to one thing or another, suddenly, no hooks appear in the Hookmark command palette.
could you please try doing Copy Link or Copy As Markdown Link. Does the URL match what is in the browser?
Can you find the URL in the Bookmarks window?
if you access the same web page in Safari, do you see the links?