The October 2017 update to CAESAR has resulted in incompatibility with Kaspersky Labs Antivirus. To resolve an 'onReadyState' error, shown in the screenshot below, you must pause the Kaspersky extension in your browser. Instructions on how to do this in various browsers can be found at https://support.kaspersky.com/us/11464#block1 .
The error message will include a web address from the kaspersky-labs domain, such as the following (emphasis added):
Function 'onReadyState' Error: Failed to execute 'querySelectorAll' on 'Element': '[src="https://gc.kis.v2.scr.kaspersky-labs.com/00C56552-CC98-674D-9D45-F2ACSA241F33/main.js" charset="UTF-8"] is not a valid selector.
Keywords: kaspersky labs antivirus src.kaspersky-labs.com
Created: 2017-10-24 20:55:20
Updated: 2019-02-04 16:59:35