Morganov oh! Is that with the latest beta of C3? I think I jumped the gun and it requires features from the beta. If you can check that it works there for you as well, I'd appreciate it.
To remove the plugin, you can use the addon manager in safe mode:
To use Safe Mode, add ?safe-mode to the URL, e.g. editor.construct.net/?safe-mode. Note all third-party addons are disabled in this mode. You should immediately open the Addon Manager, uninstall the problematic addon, and then restart Construct 3. Be sure to remove the ?safe-mode part of the URL to re-enable loading third-party addons.
It is not recommended to open any projects or try to do any actual work in safe mode: it exists only so you can reach the Addon Manager dialog to uninstall the addon.