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Description of the Issue

Currently, the Document Map dock panel loads with either standard or fluent icons dynamically based on the selection via Notepad++ menu: Settings » Preferences... » Toolbar. Inspired by this feature for native dock panels in NPP, I have implemented it for all 3 of my plugins: StayAwake, Goto Line Col and FWDataViz.

Here are the preview clips of the tabs for my 3 plugin dock panels along with that for Document Map for comparison:

1. Light Mode - Standard Icons:
   

2. Dark Mode - Standard Icons:
   

3. Light Mode - Fluent Icons:
   

4. Dark Mode - Fluent Icons:
   

To be able to dynamically switch between standard and fluent icons for the plugin dock panels, I had to determine 2 different settings for Notepad++ at launch time:

1. Light or Dark mode: This is easily handled with the NPPM_ISDARKMODEENABLED Plugin Communication API message.
2. Standard or Fluent Icons: To determine this setting, there is currently no Plugin Communication API message available for plugin authors.

Describe the solution you'd like.

I propose that we should implement a new Plugin Communication API message: NPPM_GETTOOLBARICONSETMODE

Debug Information

Notepad++ v8.8.1

Anything else?

No response