Browser Actions uses JavaScript to get web page details on your behalf. To do this, it utilizes a developer feature in your browser that must first be enabled.
Table of contents:
Brave Browser
Menu View → Developer → enable Allow JavaScript from Apple Events.
Safari
First, enable the “Develop” menu by opening the Settings window (menu Safari → Settings…), going into its Advanced tab, and enabling Show Develop menu in menu bar.
Close the Settings window, then go to menu Develop → enable Allow JavaScript from Apple Events.
Chromium
Menu View → Developer → enable Allow JavaScript from Apple Events.
Google Chrome
Menu View → Developer → enable Allow JavaScript from Apple Events.
Microsoft Edge
Menu Tools → Developer → enable Allow JavaScript from Apple Events.
Vivaldi
Open the Vivaldi preferences (menu Vivaldi → Preferences…) and find its Privacy and Security section. There, enable Allow JavaScript from Apple Events.