Fonts Exclusion in Preferences

Summary:

System fonts nor user fonts can't be excluded from Inkscape, being so difficult to purify the workflow when working on a system full of work-unnecessary fonts.

Steps to reproduce:

• Open Inkscape
• Open Text Tool Dialog (Ctrl + Shift + T)
• Look at the available fonts.
• Go to Preferences (Ctrl + Shift + P)
• Go to Tools > Text
• Disable Use Inkscape's fonts directory and Use user's fonts directory
• Restart Inkscape.
• Open Text Tool Dialog (Ctrl + Shift + T)
• Look at the available fonts.

What happened?

The same fonts are available.

What should have happened?

Inkscape should exclude all fonts located on ~/.fonts and /usr/share/fonts

Version Info:

- Inkscape Version: 1.0 (4035a4fb49, 2020-05-01) (from MX Linux Test Repository)
- Operating System: MX Linux
- Operating System version:  19.1