SuttaCentral
I like to use the Pāli-English look up function but very often it doesn’t work at all (I’m on latest mac OS and firefox). But I just found a temporary fix. In Text Settings, surprisingly turning off and back on again the look up function doesn’t do anything, just continues not working. However, turning off the ‘original text’ to make the Pāli disappear completely, then turning it back on, makes the look up function work.
Thought I’d share that in case anyone else finds that useful!
For me it works the following way: When opening a page I turn the lookup tool off, refresh the page, and then turn it on again. Then it works until I have to go to another page in which case I have to repeat the whole procedure.
Firefox on Ubuntu, latest version.
Ah, I tried refresh and tried loook up tool off and back on, but not the two together. Maybe try my method to see if it works on your setup - if so it’s fewer steps!
It does indeed. But most of the time I am on Pali only (on a page that isn’t segmented), so that doesn’t help. 
Well, if it doesn’t require the refresh page step, it’s still one step shorter!
What would be nice would be a way to do this without having to scroll all the way to the top of the page to get to that menu to turn things off and on, loosing ones place in the sutta in the process!
I didn’t have to do this until now, but now that I’m looking at a Sutta with no Pāli line by line, I’ve had to go to the Pāli only page, and my method didn’t work. Yours did. That’s with Firefox on Mac.
Is there a ‘How to Use Suttacentral’ page? That would seem to be a good page to have, perhaps clearly linked at the top of the homepage? I would suggest putting these two instructions there so people can get the lookup function working. It’s a great function! So it would be great if everyone could use it. I’m sure many people currently can’t, because they don’t know this detailed step by step fix.
Also, I recently had to work out how to remove the huge side bar on the left. I found out once from this forum, maybe a year ago. But I forgot how. I tried dragging it, but no luck. My second logical choice was clicking the top section of it which is coloured in dark gray. That didn’t work, it took me to the homepage!
Finally after persisting (after having given up previously a few times), I found that the way to do it is click the menu icon on the left side of the central panel.
I am left concluding that that is really not very intuitive. Based on the fact that I’m a fairly average person who can think quite carefully; that I even once learned how to do that; and that it was still an enigma for me. I am certain that I will not be the only one having this experience.
So if that is not going to change, then perhaps an animated picture of how to do that would be great on the potential ‘How to Use Suttacentral’ page.