I then guess something is wrong with my langs.xml (on my work computer). The settings work just fine on my private computer. I’ll check on that and report back.

If anyone is interested (thanks @Michael-Vincent for pointing this out), the property tabSettings in /NotepadPlus/Languages/Language is set to “-1” if the “Use default value” is use. When this checkbox is disabled the value is then determined by the configured tab size and is incremented by 128 if the “Replace by space” option is set.

goto %APPDATA% directory and rename notepad++ directory temporarily.
Start npp, it will recreate new, with default settings set, config files.
Do your changes and make your test to see if it keeps it settings.

So take heart, OP, I think that I agree with your findings!

I no longer agree. :-(

If one follows my earlier outlined procedure, they will (and I, finally) realize that what I did…does nothing. All I do is remove the “default” setting from being applied to XML files. Well…if the setting then left for XML files happens to match the “default”, what has been altered: NOTHING (that matters for the current discussion).

Anyway, apologies for the confusion – seems to be working just fine for me now to save the settings between Notepad++ runs.

I’m in local config mode:

Notepad++ v7.8.6 (64-bit)
Build time : Apr 21 2020 - 15:23:03
Path : C:\usr\bin\npp64\notepad++.exe
Admin mode : OFF
Local Conf mode : ON
OS Name : Windows 10 Enterprise (64-bit)
OS Version : 1809
OS Build : 17763.1158
Plugins : AnalysePlugin.dll AutoSave.dll BetterMultiSelection.dll ChangedLines.dll CodeAlignmentNpp.dll ColumnTools.dll ComparePlugin.dll CsvQuery.dll CustomizeToolbar.dll DoxyIt.dll DSpellCheck.dll Explorer.dll GitSCM.dll JSMinNPP.dll NppConsole.dll NppConverter.dll NppEventExec.dll NppExec.dll NppExport.dll NppFTP.dll NppMarkdownPanel.dll NppMenuSearch.dll PreviewHTML.dll Python Indent.dll QuickText.dll SpeechPlugin.dll SurroundSelection.dll TagLEET.dll XMLTools.dll ZoomDisabler.dll

I use “Replace by space” “4” and only override that in Makefile:

That always stays for me opening and closing N++ and through reboots.

I think it stores it in $(NPP_INSTALL_DIR)\langs.xml

PS MVINCENT ~ > grep tabSettings C:\usr\bin\npp64\langs.xml
        <Language name="makefile" ext="mak" commentLine="#" tabSettings="4" />
        <Language name="python" ext="py pyw" commentLine="#" tabSettings="-1">
        <Language name="yaml" ext="yml yaml" commentLine="#" tabSettings="-1">

You’ll notice Python and YAML are also in there because in a default install, they use tab and I “override” them to used the default (which I set to convert to 4 spaces):

Hope this helps?

Cheers.

PS: i LOVE pasting pictures directly into the new post text box!!!

That‘s my issue. It does not remain between sessions.

I can duplicate OP’s issue with fresh portable (Local Conf Mode : ON) N++ extraction:

• Go in and untick Use default value for xml files.
• Exit Notepad++
• Upon restart, Use default value for xml is ticked again.

So take heart, OP, I think that I agree with your findings!

That‘s my issue. It does not remain between sessions. Can you please point out, where this setting should be saved?

As @Ekopalypse said, “it works for me”:

Notepad++ v7.8.6   (64-bit)
Build time : Apr 21 2020 - 15:23:03
Path : C:\usr\local\apps\notepad++\notepad++.exe
Admin mode : OFF
Local Conf mode : ON
OS Name : Windows 10 Enterprise (64-bit) 
OS Version : 1903
OS Build : 18362.720
Plugins : ComparePlugin.dll LuaScript.dll MarkdownViewerPlusPlus.dll mimeTools.dll NppConsole.dll NppConverter.dll NppEditorConfig.dll NppExec.dll NppExport.dll NppFTP.dll PreviewHTML.dll PythonScript.dll QuickText.dll XMLTools.dll 

Yes, I think/thought so too but to illustrate what he did it is needed, isn’t it?
Seems I’m drawing a blank, again !? (not sure if this is the correct translation but sounds nice :-)

I suppose what the OP was trying to point out with the redboxing was that the item was the only one that was altered.

this seems to work for me as long as I’ve understand correctly what
you are trying to achieve.

Notepad++ v7.8.6   (64-bit)
Build time : Apr 21 2020 - 15:23:03
Path : D:\Tests\npp\_latest\x64\notepad++.exe
Admin mode : OFF
Local Conf mode : ON
OS Name : Windows 7 Professional (64-bit) 
OS Build : 7601.24544
Plugins : mimeTools.dll NppConverter.dll NppExport.dll 

as far as I understand @Daniel-Fuchs default is repalce by space.
Unchecking use default value and not having checked Replace by space
would use tabs for xml documents. Am I wrong?

Is there any reason you redboxed Use default value in your screenshot?