runtime.getFrameId()
Returns the frame ID of any window global or frame element when called from a content script or extension page, including background pages.
Syntax
js
let gettingInfo = browser.runtime.getFrameId( target // object)
Parameters
target
AWindowProxy or abrowsing context containerElement (iframe, frame, embed, or object) for the target frame.
Return value
Returns the frame ID of the target frame, or -1 if the frame doesn't exist.
Examples
This code recursively walks descendant frames and gets parent frame IDs.
js
const parents = {};function visit(win) { const frameId = browser.runtime.getFrameId(win); const parentId = browser.runtime.getFrameId(win.parent); parents[frameId] = win.parent !== win ? parentId : -1; try { const frameEl = browser.runtime.getFrameId(win.frameElement); browser.test.assertEq(frameId, frameEl, "frameElement id correct"); } catch (e) { // Can't access a cross-origin .frameElement. } for (const frame of win.frames) { visit(frame); }}visit(window);