Lansweeper used to use an NPAPI plugin to run actions in Firefox. As recent Firefox releases no longer support NPAPI plugins, a new plugin was released. If you are still using the old plugin, uninstall it under about:addons in Firefox and install the new plugin by following the steps below.
To configure Mozilla Firefox to run asset and user actions, do the following:
Open Firefox, access this link and, if prompted, click Allow and Install. This will install the plugin required to run asset and user actions.
Restart Firefox. To ensure that Firefox is fully stopped before restarting, you can open Windows Task Manager (Ctrl+Shift+Esc), right-click the firefox.exe process(es) under Processes and select End Process.
You can check whether the plugin is properly installed by accessing Firefox's Add-ons menu. You can access it directly by using the Ctrl+Shift+A shortcut. You can disable/re-enable the plugin from here as well.