Is it possible to change/convert a single button or popover button once created on a layout to a single button bar button?
No. Just recreate it as a one button, button bar. I have to assume you want to change a bunch of buttons because it takes about 10 seconds.
Lately I've only used button bars, even for just one button, as I have the option of taking advantage of naming the button via calculation.
Yes I realize the advantage of the button bar hence why I was seeking an easy way to convert all my single buttons and popover buttons.
I also prefer a single-button button bar to an old style button for the reason Steve gives, but also because it gives the option of adding further button segments in future if needed. And I agree it is annoying that you can't convert an existing button into a button bar, but at least it's easy enough to replace them one by one as needed.
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