Hi morpheen, does the add-on entry show on the right-click context menu? If so, do the buttons display when you click the item? If so, do any of the buttons work or are they all nonresponsive?

For personal support, please contact me on Github at https://github.com/jscher2000/Save-webP-as-extension/issues or by email at jscher2000@outlook.com.

(Update: version 1.5.1 pops up a little panel with some more options when the script is denied permission to read the page. Previously that just caused silent failure.)