Kubuntu use OCR: https://www.reddit.com/r/Kubuntu/comments/11dut0s/kubuntu_use_ocr/

ocr.sh

#!/bin/env bash 
# Dependencies: tesseract-ocr flameshot imagemagick xclip

#Name: OCR Picture
#Fuction: take a screenshot and OCR the letters in the picture
#Path: /home/Username/...

#you can only scan one character at a time
SCR="/home/Username/pictures/SCR"

mv $SCR.png $SCR.prev.png
# take a shot what you wana to OCR to text
flameshot gui -p $SCR.png

# increase the png
mogrify -modulate 100,0 -resize 400% $SCR.png 
# should increase detection rate

# OCR by tesseract
tesseract $SCR.png $SCR &> /dev/null -l eng+chi_sim

# get the text and copy to clipboard
cat $SCR.txt | xclip -selection clipboard

exit