Are you sure the `src/external-link-symbolic.svg` is going to work? Seems you are using icon name, not the file path. Also, the file is not in correct path.

I'm going to approve this since you have `src` added as icon theme but the correct symbolic folder should be something like: ``` extension@extensionfolder └── icons └── hicolor └── scalable └── categories └── external-link-symbolic.svg ```

Thanks! Yes, it works. The thing is I prefer not to hard code bundled symbolic icons. Reason for it is that if host system uses different icon set (like Ubuntu Yaru) bundled icon will look out of place and inconsistent. As I already pointed it out in matrix this particular icon is missing from Gnome default icon set. There is similar icon bundled inside libadwaita, but digging deeper and talking to guys over libadwaita matrix I understood that those icons are primarily used for about dialog and other adwaita specific internal resources and currently not intended to be exposed for wider usage.