On mac os (12.2.1) the Arial font is not loaded due to a name problem with the font file. To fix it I changed the line 102 in my local file flowkey_dl.py with :
fnt = [ImageFont.truetype("Arial.ttf", sz) for sz in font_size]
This font issues with different platforms is really annoying. I hope I found a solution that works cross platforms now, based on matplotlib font_manager. If it does not work, please open new issues.
On mac os (12.2.1) the Arial font is not loaded due to a name problem with the font file. To fix it I changed the line 102 in my local file flowkey_dl.py with :
fnt = [ImageFont.truetype("Arial.ttf", sz) for sz in font_size]