I give it a good old knead until it's good and elastic, although I have never got it to stretch thin enough for the window pane effect (close, though). That's how I've been proving it too, following this recipe and method:
www.bbcgoodfood.com/recipes/sourdough-bread/amp
Not entirely convinced it needs the honey in there.
Knead it until you pull it apart and you can see it's really thin. If it tears before it gets thin it needs more kneading (my mate does a no knead method. You only fold the dough a few times between provings but it takes a lot of time to make).
I leave my starter out of the fridge overnight, Friday, make a leaven the following morning, Saturday and leave it 9 to 11 hours to rise.
Mix the flour, water and salt; knead 20 to 30 mins by hand or use a mixer.
Leave in mixing bowl covered with cling film between 3.5 and 4 hours to rise.
Knock it back then place in a floured banneton and leave in the fridge overnight and cook Sunday morning. No tea towel required.
Sugar, or honey, is added to make the crust firmer but I can't tell the difference so don't use any.
Took me a year to get the knack and even gave up for a while because my dough was really sticky and I didn't know what to do. Keep at it because it's rewarding. My mate's rosemary and sea salt focaccia is to die for, especially with olive tapenade.