@leocg My apologies- i misspoke- i do get the cube icon of course,
but i was mystified by your feedback, until i realized that your wording was misleading (too).
One doesn't click on the extension's icon- that does nothing. One clicks on the pin icon itself to accomplish the pinning.
A label, like "Click here to pin icon to address bar" would've helped! No thanks to Opera for that bit of mystifying lack of documentation.
Thanks for the tip!
Infinice
I