Description of the Issue

1. [bug to fix] Shortcut mapper links control-d to SCI_SELECTIONDUPLICATE but it should map to SCI_LINEDUPLICATE instead.
2. [fyi] Menu command Edit->Line Operations->Duplicate Current Line does invoke SCI_LINEDUPLICATE, however the shortcut shown under Edit->Line Operations->Duplicate Current Line says control-d. Cosmetically this is OK.
3. [bug to fix] SCI_SELECTIONDUPLICATE isn't available to be mapped to a customized button.

Steps to Reproduce the Issue

1. Select multiple lines of text and do control-D. The multi-line selection gets duplicated.
2. Select multiple lines of text and do Edit->Line Operations->Duplicate Current Line. The single line where the cursor is at gets duplicated.
3. Go to Customize Toolbar toolbar plugin and under "Available toolbar buttons" double-click on "Duplicate Current Line."

Expected Behavior

I expected to press the custom button and have it emulate control-d (SCI_SELECTIONDUPLICATE), because control-d is what the GUI shows.

Actual Behavior

Pressing the custom button does SCI_LINEDUPLICATE.

Debug Information

Notepad++ v7.5.9 (32-bit)
Build time : Oct 14 2018 - 15:02:52
Path : C:\Program Files (x86)\Notepad++\notepad++.exe
Admin mode : OFF
Local Conf mode : OFF
OS : Windows 10 (64-bit)
Plugins : DSpellCheck.dll mimeTools.dll NppConverter.dll NppExport.dll CodeAlignmentNpp.dll JSMinNPP.dll MarkdownViewerPlusPlus.dll NPPJSONViewer-win32.dll NppTextFX.dll PluginManager.dll Tidy2.dll _CustomizeToolbar.dll

notepad-duplicate-current-line.zip

Screen recording is in attached file notepad-duplicate-current-line.zip which can be viewed with Screencastify on Chrome or using VLC media player.

Yes, I know how confusing this is. :D There are two bugs to fix.

You can see original discussion between me and Meta Chuh by going here.