Featured image : build error when the folder name contain a capital letter or an underscore

[mlo-3]

Hi,

I noticed that Zola stop building and report a file not found error for a featured image when the folder contain a capital letter or an underscore in its name and a featured image is called in the index.md :

Error: Reason: resize_image: Cannot find file: "file path and name"

It works fine when no capital are in the folder name.