Great idea - I ended up experimenting to improve the ocr accuracy:

    #!/bin/bash

    screenshot=$(mktemp)
    decoded_data=$(mktemp)
    processed_data=$(mktemp)

    cleanup() {
        rm "$screenshot" "$decoded_data" "$processed_data"
    }

    trap cleanup EXIT

    flameshot gui -s -r > "$screenshot"

    convert "$screenshot" \
        -colorspace Gray \
        -scale 1191x2000 \
        -unsharp 6.8x2.69+0 \
            -resize 500% \
        "$screenshot"

    tesseract \
        --dpi 300 \
        --oem 1 "$screenshot" - > "$decoded_data"

    grep -v '^\s*$' "$decoded_data" > "$processed_data"

    cat "$processed_data" | \
        xclip -selection clipboard

    yad --text-info --title="Decoded Data" \
        --width=940 \
        --height=580 \
        --wrap \
        --fontname="Iosevka 14" \
        --editable \
        --filename="$processed_data"