Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

element.openOrClosedShadowRoot property always returns null

  • 1 cavab
  • 0 have this problem
  • 1 view
  • Last reply by cor-el

more options

Hello, I'm trying to use https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/dom/openOrClosedShadowRoot functionality in an extension but the element.openOrClosedShadowRoot always returns null.

Also is there a place in Firefox Devtools console (similar to the Chrome Devtools dropdown) to switch the context from the user console to the extension console so we can try extension only APIs?

Thanks.

Hello, I'm trying to use https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/dom/openOrClosedShadowRoot functionality in an extension but the element.openOrClosedShadowRoot always returns null. Also is there a place in Firefox Devtools console (similar to the Chrome Devtools dropdown) to switch the context from the user console to the extension console so we can try extension only APIs? Thanks.

All Replies (1)

more options

Open about:debugging and go to "This Firefox" and click the Inspect button next to the extension.