Depends on how much do you trust browser extensions. From my knowledge every extension code can be inspected and read unless the code is obfuscated. The styles are written in CSS (only a few lines) and injected into the website. So you can quickly review it.
If you want to be extra cautious you could write your own extension to be safer, but I trust it good enough.
If you want to be extra cautious you could write your own extension to be safer, but I trust it good enough.