ernestdefoe You have custom CSS that changes the background of the buttons. You need to change the text color as well if you want to do that. This is not caused by this extension's code.
This is the code affecting it (in dark mode, but I assume it's a similar thing for light mode):
.Button:not(.Button--flat, .App-header .Button, .App-header .Button:hover, .UserCard .Button,
.UserCard .Button:hover, .Button--primary, .Button--link, .FoFLogInButton, .SubscriptionMenu-button--follow),
.Select>.Select-input {
border:1px solid transparent;
background:padding-box linear-gradient(#fff, #fff),border-box linear-gradient(#e5e5e5 90%, #ccc 100%),border-box #fff
}
