Inserting tags in textboxes using the right-click context menu may insert tag at the wrong location

Using the right-click context menu to insert tags into a textbox, e.g., the SMS Message textbox on the Workflow Actions wizard may insert the tag at the wrong location.

For example, if the textbox has a single line of text then right-clicking the mouse below the text but to the left of the end of the text would not insert the tag at the end as expected, if would insert it in the existing text based on the X position of the mouse pointer.

This can easily be seen by right-clicking the mouse and then pressing escape to cancel the context menu. The insertion point should move to the location in the text where the mouse was clicked or, if it was clicked beyond the text, the insertion point should be positioned at the end of the text.