Icon file is missing.

While toppler 1.1.6 hat an application icon file toppler.xpm, the code checked out from this directory does not provide, nor generate upon make, an icon fileto be used for menus in desktop environments or desktop shortcuts.

I suggest to re-add an icon file.

A workaround so far is to manually use the icon file from toppler 1.1.6, as described → here.