You can create a folder named "test", put:
manifest.json:
{
"mod" : {
"schema_version" : 2,
"payload" : {
"app_icon" : [ {
"id" : "app_icon_01",
"name" : "Test",
"path" : "app_icon1.png"
}
]
}
},
"manifest_version" : 3,
"name" : "Test",
"icons" : {
"512" : "icon_512.png"
},
"version" : "1.2.1"
}
in it, put icon_512.png and app_icon_01.png (290px x 290px) in it, goto the URL opera://extensions, turn on developer mode, click "Load unpacked" and point it to the test folder to load the extension.
Then, you can goto the URL opera://configure/mods/interface/app_icon, set the mod's icon and restart Opera.
Then, Opera's pinned taskbar icon should be that custom icon.
