Tutorial: How to change line icons without strokes
This video explains how to adjust line width in icons, which are made of filled paths.
You can re-create strokes from expanded lines or just use a fast shortcut to make the lines thinner. It would be useful if you want to combine icons of different sizes but with the same stroke width. Like a small 24px icon with 2px stroke and a bigger 48px one that also has a 2px stroke.
Free icons: https://icons8.com/icons