Undefined index – Debug

Hi !

I just want to report an error I just had
(I have Wp_debug enabled)

Undefined index: bt_kw_desc_font_size in /home/…/wp-content/plugins/bluet-keywords-tooltip-generator/add-style.php

(the link is truncated)

Hoping it can help to improve your great plugin !

https://ww.wp.xz.cn/plugins/bluet-keywords-tooltip-generator/