List currently focused Firefox tabs

list-focused-fftabs.py

#! /usr/bin/env python3

"""
List all Firefox tabs with title and URL

Supported input: json or jsonlz4 recovery files
Default output: title (URL)
Output format can be specified as argument
"""

import sys
import pathlib
import lz4.block
import json

path = pathlib.Path.home().joinpath('.mozilla/firefox')
files = path.glob('*default*/sessionstore-backups/recovery.js*')

try:
    template = sys.argv[1]
except IndexError:
    template = '%s (%s)'
    
for f in files:
    b = f.read_bytes()
    if b[:8] == b'mozLz40\0':
        b = lz4.block.decompress(b[8:])
    j = json.loads(b)
    list_focused_fftabs(j)
    
def list_fftabs(j):
    for w in j['windows']:
        for t in w['tabs']:
            i = t['index'] - 1
            print(template % (
                t['entries'][i]['title'],
                t['entries'][i]['url']
                ))
                
def list_focused_fftabs(j):
    for w in j['windows']:
        t = w['tabs'][w['selected']]
        i = t['index'] - 1
        print(t['entries'][i]['url'])