I use Flameshot combined with Tesseract and zbarimg to quickly clip areas of the screen and either OCR them or decode barcodes, which I then map to hotkey combinations.
For example, I have `bash -c 'flameshot gui -s -r | tesseract - - | gxmessage -title "Decoded Data" -fn "Consolas 12" -wrap -geometry 640x480 -file -'` mapped to Super+O, so I can just press the key combo, select a region of the screen, and have the OCRed text immediately displayed in a dialog box from gxmessage (which accounts for most of the command line). Replace 'tesseract' with 'zbarimg' and you have a barcode scanner.
For example, I have `bash -c 'flameshot gui -s -r | tesseract - - | gxmessage -title "Decoded Data" -fn "Consolas 12" -wrap -geometry 640x480 -file -'` mapped to Super+O, so I can just press the key combo, select a region of the screen, and have the OCRed text immediately displayed in a dialog box from gxmessage (which accounts for most of the command line). Replace 'tesseract' with 'zbarimg' and you have a barcode scanner.