If the Line change indicator option is enabled in the "View" tab, modified lines will be indicated with a special colored shading between the line numbers and the first character on the line. The colors used to indicate saved and unsaved changes to a file within an editing session can be configured in the Manage themes dialog. If the undo buffer is cleared during an editing session (for example, by a revert to saved command), the line change indicators would be reset as well.
If this option is toggled in the View tab, this will only affect the active document. Global changes for this feature are set in the Editor display » Line change indicator section of Settings.
If a file is opened that exceeds the threshold specified for using temporary files in the File handling » Temporary files section of Settings, and the option is set to open without a temporary file in this case, the line change indicator will not be displayed.
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