[gindely]

Since you deny a weird context switch for your eyes, are these actually inline elements? That would imply the size of the containers is changing. Which would surely be a weird context switch. But at least I can have no doubt what my action is about to affect - I get frustrated on sites when it says "you're about to delete these items" and i have no idea whether it agrees with me about which items I'm about to delete or not.

But if they're overlaid elements, like a context sensitive menu that contains two options - delete, cancel - is there any substantive difference between a menu and a modal? The main advantage of a classic menu over a modal seems to be that it has a implicit cancel option that is uniformally implemented. But nowadays, menus are implemented without toolkit support - yay dom, yay - so even that is not consistent.

[winrid]

This is what I mean: http://imgur.com/a/hY9eM77

Content size doesn't change in my case and I would highly advise against changing the sizing of elements on the page for something like this.

The buttons are sized vertical based on the content up to a limit.

[gindely]

Yep okay, so I guess that's not inline by my definition (since it overlays the text). I have definitely seen webpages that change the size of the containing box to add in the confirmation message and buttons.

I guess it's an between case I didn't consider - it's maybe not modal with respect to the whole app, but it seems to be modal with respect to that one comment (you can ignore it and do something else with the rest of the program, but with that comment, you can't even read it).