Unveilhooks tries to load page in data-link as css

[futtta]

Describe the bug
The WordPress core "gallery" block adds a data-link attribute to images with the link to the attachment page which lazysizes+unveilhooks tries to load assuming it is CSS.

To Reproduce
Example HTML as generated by WordPress Gallery block is at https://gist.github.com/futtta/ee0f5eeedbdba0d884ac1376def3d6f6

Steps to reproduce the behavior:

1. In WordPress create a post/ page with the block editor, adding a gallery block.
2. Install Autoptimize (which uses Lazysizes with Unveilhooks) and enable lazyload (settings -> autoptimize -> images -> lazyload checkbox)
3. load the page/ post and observe the network activity to see how the attachment page is being loaded by unveilhooks

What is the expected behavior
Attachment page is not loaded.

What happened instead
Attachment page is loaded.

In what environment (browser/device etc.) does this bug happen/not happen:
Happens in all if lazysizes+unveilhooks is active.

[futtta]

[futtta]

I'm working on Autoptimize 2.7, in which I am going to fix this with a small workaround by excluding img tags from honoring data-link attributes in unveilhooks, changing

    tmp = target.getAttribute('data-link');
    if(tmp){
        addStyleScript(tmp, true);
    }

into

    tmp = target.getAttribute('data-link');
    if(tmp && target.tagName.toLowerCase != 'img'){
        addStyleScript(tmp, true);
    }

[aFarkas]

@futtta
The probably best way to fix this issue is to "namespace" every attribute or make them configurable, but I fear it is too late for that as a default.

Maybe as a workaround I could introduce a variable

[futtta]

a variable by which to exclude? that would indeed work I guess.