New issue I’ve not seen before. If I Hook something (a webpage, file, etc.) to an Omnifocus task or project, the Hookmark link is broken when the Omnifocus item is moved or the title is altered.
What version of OmniFocus are you using?
I can’t replicate this and would surprise me. If it is a bug it is with OmniFocus. It is OmniFocus’s responsibility to open the link. E.g., here is a OmniFocus link:
omnifocus:///task/i-VGw6of8o3. I can move the target task around and OmniFocus honours the link.
I’m using the Omnifocus beta, which could be the issue. However, I’m also having the same issue with hooked Obsidian files.