The Lock Indicator

The Lock Indicator is an icon which is displayed in the upper right corner of the main writing screen.
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By default the lock indicator is not visible and the element text on the writing screen can be edited and changed. The corresponding element is marked as "In Progress".

Selecting the Mark Done item from the main menu will lock the text and mark the corresponding element as "Done".
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If the lock indicator is visible, then the element text cannot be modified. The corresponding element is considered Done.

Selecting the Mark In Progress item from the main menu will unlock the text and make the corresponding element as "In Progress".