Wow!
A revolutionary feature in TW 5.4.0 is two new attributes for linkwidget startactions and endactions on drag-drop links. (Same for list-tagged-draggable, list-links-draggable)
While there are few examples in official documentation, but I like to see more applied examples from developer and experienced users.
The link-widget documentation contains an example how to use it. See: Action Variables section.
It is basically used in the same way as “button actions”. The difference is, that the actions are “triggered” on “drag-start” or “drag-end”.
The list-links-draggable and the list-tags-draggable macros have “internal” drag-start and drag-end actions.
The new ones are additional user actions, that can be used on demand. Where demand varies on the use-case.
Help is very welcome here. If you stumbled upon a missing “drag-??” feature in the past, please let us know about your use-case.
I just found out, that a link to the the modifier variable may also be useful.
Intriguing! At the bottom of that tiddler, there’s a neat little demonstration of how modifier keys are recognized within the browser.
I have no idea if this problem is on TiddlyWiki’s side, or whether it’s caused by something deeper in browser or OS: On my Mac each modifier (except Ctrl) tests fine by itself, but combinations that should count as meta-alt and meta-shift produce normal message (alt-shift combo is fine).
(The Control key, and any combo with that key, also doesn’t register in any way on that page, but that’s understandable, because Mac OS apps immediately intercept Ctrl for contextual menu.)
You will need to create an issue at GitHub. We need someone, that has one or more i-devices, to replicate the problem.