Webapps icons don't appear

[wokawoka]

I've just read that you have ceased the development of the plug-in ... then I'm writing just to ask you a suggestion.
The extension works good and I find it really very useful, unfortunately I can't get the icons of many websites I want to add to show on the buttons (basically the buttons are there but without an icon they are invisible, a tooltip with the name correctly appears when I'm hovering over it).
Since I've read a similar comment on your website written by an user many years ago, I thought that it could be linked to a known problem.
I'm using an updated version of Thunderbird (45.5.1).
Thank you very much!

EDIT:
The behaviour seems inconsistent: it seems that some website icons are added, for example the icon of www.meetup.com works, while the icon of mail.yahoo.com does not appear. Could this misbehaviour be linked with the actual icons properties?

[geekley]

@wokawoka If you want, you can download the fix I made for the icons:
https://github.com/geekley/WebAppTabs/releases/tag/release_2.1-icon-fixed