https://www.w3.org/TR/webdriver/#get-computed-label

Current spec:

12.4.10 Get Computed Label
HTTP Method 	URI Template
GET 	/session/{session id}/element/{element id}/computedlabel

The remote end steps are:

    If the current browsing context is no longer open, return error with error code no such window.

    Handle any user prompts and return its value if it is an error.

    Let element be the result of trying to get a known connected element with url variable element id.

    Let label be the result of a Accessible Name and Description Computation for the Accessible Name of the element.

    Return success with data label. 


Tests:

imported/w3c/webdriver/tests/get_computed_label/