KiYugadgeter KiYugadgeter - 26 days ago 6
JSON Question

Why webextension installation failure?

I am learning how to write webextensions.

so I'm copying "beastify" extension from here from scratch.

But my copied version's installation failure.

I don't know why installation is failure.

There are same directory structure, same meaning code, same picture file.

I suppose there are causes of installation failure in manifest.json.

my manifest.json:

"manifest_version": 2,
"name": "Beastify",
"version": 1.0,

"description": "add a browser action icon to the toolbar. Click the button to choose a beast. The active tab's body content is then replaced with a picture of the choosen beast.",
"icons": {
"48": "icons/beasts-48.png"

"permissions": [

"browser_action": {
"default_icon": "icons/beasts-32.png",
"default_title": "Beastify",
"default_popup": "popup/choose_beast.html"

"web_accessible_resources": [


The value of version must be string.
Please replace "version": 1.0, to "version": "1.0",.