What causes the mail composition page to expand in Sequoia?

[Rod]

Yes, it's new in Sequoia, as far as I can tell.

I don't know what you mean by this:

I didn't do anything to make it happen. It's part of Sequoia.

You must somehow be triggering a double click in the menu bar. That's how it works. No other way I know of, unless there is some setting in Accessibility that you have changed from the defaults.

About all I can suggest is that you use the Accessiblity function to change the double click speed down so that whatever you are doing, or your trackpad / mouse is doing won't trigger it. I don't use multi-finger gestures as I have always found them too inconsistent in operation, so I can't help you there.

I tried this for another OP, same topic. In macOS Sequoia if I reduce the size of this window (the one I'm writing this reply in) manually, then double click in the Tab bar it becomes maximum sized again (the way I like it), double clicking again returns it to the size I reduced it to earlier.
I find this a really handy feature especially when creating screen shots. My screen shots go to my Desktop so if I want to view or edit one I can quickly reduce the browser window to a pre-set size where I can see my screen shots, edit or view them then return quickly to max size and attach the screen shot to a post. It's much faster than manually resizing or using Mission Control via Hot Corners.

Tiling is a completely different feature new in Sequoia which is not that useful to me on a MBP but I can imagine would be very useable on a desktop;

Tile windows on Mac

Quickly arrange windows on your Mac by dragging them, using menu options or using keyboard shortcuts.

support.apple.com

 

[MacInWin]

Rod, good example! I was responding to this:

More info. This only works when the window touches the top bar, whatever that is called. If the window is lower it just moves up but retains its size. I tried this with a small RTF file.

One of the "triggers" for tiling is to drag the window to be tiled to the screen edge. So, when @rbpeirce drags a window up and touches the Top menu, I think that is what triggers it to be "tiled" to be large. I'm still experimenting with tiling and don't know exactly how it works, but it does say that when the window reaches screen edge, it tiles.

I do like your use case. I do screenshots a lot and your workflow would work well for me. Now all I have to do is remember it!

 

[Rod]

Yes, remembering thats a problem. By the by you can use the same technique not only/just to view the desktop but other windows behind the active one;



Neat huh?

 

[rbpeirce]

That is, I think, what is called "tiling."

Tile windows on Mac

Quickly arrange windows on your Mac by dragging them, using menu options, or using keyboard shortcuts.

support.apple.com

Also new on Sequoia.

Could be. Whatever, it was a bug until I could figure out how to make it a feature