Created attachment 155502 [details]
When multiple paths are selected, the Scale Styles option is not activated.

SUMMARY
A bug where Scale Styles is not activated when "multiple" vector paths are selected.
When one path is selected, the Scale Styles option is activated, but when multiple paths are selected, the Scale Styles option is not activated.

STEPS TO REPRODUCE
1. Add a vector layer.
2. Choose the Freehand Path Tool.
3. Draw a path.
4. Choose the Select Shapes Tool.
5. Select the path. This will activate the Scale Styles option in the Tool Options.
6. Choose the Freehand Path Tool again and draw another path.
7. Choose the Select Shapes Tool again.
8. Select both paths.

OBSERVED RESULT
The Scale Styles option is deactivated, and the Scale Styles option cannot be unchecked.
When you resize the paths, the thickness of the paths changes.

EXPECTED RESULT
The Scale Styles option is activated, so you can check or uncheck the Scale Styles option.
If you uncheck the Scale Styles option and resize the paths, the paths will retain their thickness.

SOFTWARE/OS VERSIONS
Build ABI: x86_64-little_endian-llp64
Build CPU: x86_64
CPU: x86_64
Kernel Type: winnt
Kernel Version: 10.0.19044
Pretty Productname: Windows 10 (10.0)
Product Type: windows
Product Version: 10
Qt Version: 5.12.12

ADDITIONAL INFORMATION