Keeping the dialog.js clean as discussed in #1667742: Add abstracted dialog to core (resolves accessibility bug).
How about renaming dialog.js to dialog.api.js and having the new file be dialog.js?
will probably close this one for #1851414: Convert Views to use the abstracted dialog modal where we can split things up. But agreed, dialog.ajax.js was a pretty bad naming in this case.
Could it be that the dialog itself is sort of idenpedent to drupal, so what about dialog.drupal.js and dialog.js,
but sure names aren't the most important thing. Way more important is that it's easy to use, so we don't end up with so many implementations in contrib/custom code again.
This was split out already as part of #1870764: Add an ajax command which makes it easy to use the dialog API in complex cases.
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