True Vector Fill.

As you may know, the fill bounded areas tool (U) in Inkscape, fills based upon the zoom level.

It leaves a small gap between the created fill and the bounded area.

I have tried for a some time ( and mostly failed ) to make a tool to find intersects and create a true vector fill.

However, it turns out a simple method already exists !

A user recently asked a question and posted a link to a youtube video.

https://inkscape.org/forums/questions/using-the-division-tool-path-menu/

https://www.youtube.com/watch?v=TbiA7c6ggzw

All that is required is: 

1. Create a rectangle and send it to the back of the stack. Object>Lower To Bottom

2. Select the objects you want to fill.

3. Copy, then paste in place, Edit>Paste In Place 

4. Combine path on those objects. Path>Combine

4. Selected the newly created combined path and the rectangle.

5. Choose Path>Division.

6. Done - fill the new object sections as you like :)

The video attached shows a abbreviated version of the above.

I've used an extension to randomise the fills, to save time in the video.

Thanks to the original poster Beton Bon, and the Original Video Maker - One Skill PowerPoint Tutorials

The moment I realized the bucket fill bounded areas tool was creating separate objects I was not a fan of the redundancy and I don't know that I'll come to need to use it.  However before I stopped using that tool I always used these settings for a perfect fill where the stroke covered completely any small gaps between the fill and the stroke.

Fill by | Visible Colors | Threshold 50 | Grow/shrink by: 0.50 | px | Close gaps: | small

IMHO these *should* be the tools default settings.  Especially the default threshold is Wayyyyy off from real world use cases.