Default icon extensions. This array includes .png and .xpm.
PNG is recommended format.
XPM is kept for backward compatibility.
Note: Icon Theme Specificiation also lists .svg as possible format,
but it's less common to have SVG support for applications,
hence this format is defined as optional by specificiation.
If your application has proper support for SVG images,
array should include it in the first place as the most preferred format
because SVG images are scalable.
Default icon extensions. This array includes .png and .xpm. PNG is recommended format. XPM is kept for backward compatibility.
Note: Icon Theme Specificiation also lists .svg as possible format, but it's less common to have SVG support for applications, hence this format is defined as optional by specificiation. If your application has proper support for SVG images, array should include it in the first place as the most preferred format because SVG images are scalable.