Not writing cookie in web_accessible_resources html page

I’m working on an add-on with a video player. Video player is a separate html page. I added it to the “web_accessible_resources” property.

And everything seems to work. Except one - it is impossible to create cookies.

I experimented with permissions:

	"permissions": [


But nothing helps. I can not create cookies in the standard way:

document.cookie = "name=test";

either using an api browser

chrome.cookies.set({value: 'test', url: '/', name: 'name'})

Nothing helps. Cookies do not appear in the inspector.

This problem arises exclusively on the page (it opens in a new tab at moz-extension://<addon-id>/player/index.html). In the content script, cookies are created as expected