Lighten the annotations inside a pdf
Okular will use the stroke color of some annotations for the box with the annotation text. If the stroke is a dark color, the text will not be readable
You can install it with pip:
pip install pdf_lightner
Or you can install it from the source
pip install .
To lighten a pdf:
pdf_lightner lighten PATH_TO_PDF
It will create a new file with _ligthen added to the name of the file.
To get more info
pdf_lightner -h