Feedback on the view-transition support

[GrimLink]

When checking this module I noted a few issues with the view-transition support.

1. BFCache Support: I noticed view transitions are disabled for BFCache restores. Could we consider enabling this? A simple fade-in on a page restore would be a nicer user experience enhancement without any apparent downside.
2. prefers-reduced-motion: The prefers-reduced-motion wrapper seems unnecessary for a simple fade, as this type of animation is generally considered safe for users sensitive to motion. We should probably only use it for more significant animations.
3. Theme Integration: The default Mage-OS theme already provides view transitions (see issue). To avoid code duplication, we should rely on the theme's implementation rather than adding it here.
   • As a extra note on this while Hyvä ships this now as a experimental feature, we are moving this into the theme part of the CSS, so same as with the Mage-OS admin theme

[rhoerr]

Thanks for the pointers and insight.

On point 1, this is possibly all perception on my part and not how it actually is: I added the bfcache cancel of transitions after testing the bfcache feature and noticing it felt slower with them on. Without transitions, jumping back or forward renders almost instantly--snaps into place. With transitions, it goes through a fade before the new page is fully visible and interactive. That's not long, maybe 400ms?, but it felt impactful.

I did add a setting to toggle that behavior, in case a site considers the transition worth it.

I'm open to better ideas on how to handle this, or data that it's not a factor to begin with. I think it's possible to customize the transitions, so many we could do a really fast one instead when traversing. That might be excessive though. Or we could ask Gilberto for thoughts from the browser side.

Point 3 follows 1. I had the transition rule in css previously, and am happy to return that, but that means no feature flag then, for better or worse. I like the idea of covering all themes so Magento's default admin theme and all other themes can benefit too. I'm hoping this module can be an easy obvious addition to all Magento instances, not just tailored to Mage-OS and Hyva with the state of the art (and understanding Hyva already has half of this built in).

[GrimLink]

I have not seen this yet, but I will check for sure 😉
But if this is the case then it makes 100% sense, to have this options.

As for point 3 maybe split the logic for the admin and the frontend options, lets say the admin is using the Mage-OS admin theme then I would like to disable this for that case.

[rhoerr]

Points 2 and 3 addressed by PRs #12 and #11 respectively. Thank you for that.

Leaving this open for analysis and decision about bfcache traverse transitions.

[gilbertococchi]

I get your point about the delay on 1), but to be honest the small delay by Cross-Doc VT is also present when going from PLP to PDP, even when the page is Prerendered.

I can say that they are some efforts to reduce the delay introduced by CrossDoc VT as it's taking a snapshot of the current page and paint holding may attribute 30-50ms (max) or so (I don't believe they delay should be around 400ms).

I like the approach to give developers control on these.

Having said that I am not sure why Back Forward navigation should not have VT while Forward with Spec Rules may have it.

[rhoerr]

Thanks for the feedback. After some discussion with others, I changed the transitions to enabled by default for bfcache traversal too. That's done as of #19.

That resolves all matters here.