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Internal plugin UI code gained a class for tracking mouse/pointer press details
What
A new internal class captures details of a pointer or mouse press for use by plugin user-interface code: the press type, column and row position (both global and local to the element), which button was pressed, and whether shift, alt, or ctrl were held.
Why
This is internal plumbing that supports building interactive plugin UI elements that respond to mouse clicks; it isn't something a reader configures directly.