iFrame of local html file is not showing anything

[fogo5]

For anyone else stumbling across this thread in search for the same answer.
There is a way to do it, as described in the parent post of this thread:

Allow to open local file

I have a closely related problem with linking files in the vault. Suppose my vault’s file structure looks like: a1.md res/abc.html res is a folder. In a1.md, I’d like an embedding of abc.html. The following attempts don’t work with either of three options (shortest path possible, relative path to file, absolute path in vault) in Preferences → File → New Link Format : <iframe src=res/abc.html></iframe> <iframe src=/res/abc.html></iframe> <iframe src=./res/abc.html></iframe> How…

<iframe src=file:///Users/yummy/path/to/vault/res/abc.html></iframe>