fatal error trying to optimize fonts

Hi Daan, I was trying to setup OMGF, and when I click Save & Optimize, I get this:

PHP Fatal error:  Uncaught TypeError: ucfirst(): Argument #1 ($string) must be of type string, array given in /sites/test.exactlywww.com/files/wp-content/plugins/host-webfonts-local/src/Optimize/Run.php:201
Stack trace:
#0 [internal function]: ucfirst()
#1 /sites/test.exactlywww.com/files/wp-content/plugins/host-webfonts-local/src/Optimize/Run.php(201): array_map()
#2 /sites/test.exactlywww.com/files/wp-content/plugins/host-webfonts-local/src/Optimize/Run.php(165): OMGF\Optimize\Run->fluent_implode()
#3 /sites/test.exactlywww.com/files/wp-content/plugins/host-webfonts-local/src/Optimize/Run.php(50): OMGF\Optimize\Run->optimization_succeeded()
#4 /sites/test.exactlywww.com/files/wp-content/plugins/host-webfonts-local/src/Optimize/Run.php(34): OMGF\Optimize\Run->run()
#5 /sites/test.exactlywww.com/files/wp-content/plugins/host-webfonts-local/src/Admin/Optimize.php(90): OMGF\Optimize\Run->__construct()
#6 /sites/test.exactlywww.com/files/wp-content/plugins/host-webfonts-local/src/Admin/Optimize.php(66): OMGF\Admin\Optimize->run()
#7 /sites/test.exactlywww.com/files/wp-content/plugins/host-webfonts-local/src/Admin/Optimize.php(43): OMGF\Admin\Optimize->init()
#8 /sites/test.exactlywww.com/files/wp-content/plugins/host-webfonts-local/src/Admin/Actions.php(49): OMGF\Admin\Optimize->__construct()
#9 /sites/test.exactlywww.com/files/wp-includes/class-wp-hook.php(308): OMGF\Admin\Actions->do_optimize()
#10 /sites/test.exactlywww.com/files/wp-includes/class-wp-hook.php(332): WP_Hook->apply_filters()
#11 /sites/test.exactlywww.com/files/wp-includes/plugin.php(517): WP_Hook->do_action()
#12 /sites/test.exactlywww.com/files/wp-admin/admin.php(175): do_action()
#13 /sites/test.exactlywww.com/files/wp-admin/options-general.php(10): require_once('...')
#14 {main}
  thrown in /sites/test.exactlywww.com/files/wp-content/plugins/host-webfonts-local/src/Optimize/Run.php on line 201

I haven’t used the plugin in a while, so I might have old data from a previous version of the plugin. Is there a way to reset the plugin or could I just remove all the omgf* options from the db?

Thanks!