Illustrator doesn’t always show Cancel button in progress dialogs for some effects, possibly Windows only
I use effects a lot, and sometimes while experimenting with appearance I get quite heavy calculations triggered (on accident or intentionally). And surely sometimes i want to cancel the execution... but these often miss it (at least on Windows).
The developer of the plugin says:
Illustrator is responsible for creating and updating the progress dialogue -- a plugin simply indicates that it wants one.
And they have it fine on Mac.
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