----------------------------------------------------------- The addon was migrated for the Firefox versions 57+. It's now more restricted: - doesn't open folders - doesn't open some URLs protocols (file:, about:, javascript:) For older addon versions use the direct installation from the GitHub repository. Read the description and install it from the releases section. ----------------------------------------------------------- This addon adds shortcuts to open bookmarks from the Bookmarks Toolbar: - Alt + 1..9,0 to open first 10 bookmarks in the same tab - Alt + Shift + 1..9,0 to open first 10 bookmarks in a new tab For Linux the Alt modifier is replaced with the Ctrl. From version 1.1.3 there are 3 variations of the shortcuts (since they are hardcoded and cannot be changed in options): - default (Windows: Alt, Alt+Shift; Linux: Ctrl, Ctrl+Shift) - lcs (Linux: Ctrl+Shift, Alt+Shift) - las (Linux: Alt+Shift, Ctrl+Shift) Check the Versions page for these. In WebExtensions standard for Windows the first modifier cannot be Ctrl because it's reserved by Firefox (changes current tab). ---------------------------- For support please use the Support Site link on this page and create an issue on the GitHub. I'll try to answer it as soon as I can. Thank you.