I don’t know if anyone else has the same problem, but it seems to me that when I change lessons, try to make a new lingQ or click on the blue button to add all the words I know it takes forever to get there. Yet, we have just updated our internet and its speed is now 10 times faster that before. I can play any movie without the problems I had in the past, but the speed on LingQ is still too slow. It may be a bit faster when I use Safari rather than Firefox, but not significantly. It was working much faster when I signed up 2 years ago. I used get through my lessons really fast, but now it takes a lot of time. Am I the only one who experiences this? Can it be fixed?
@zkaplanova - There are a couple of issues related to performance since the latest update. We are looking into these. We hope to have the site speed back to normal soon.
Yup, I can confirm this all. Changing lessons, calculating totals, lingqing, editing lings, etc - all much slower at the moment. LingQ is, unfortunately, the slowest website I use.
Hopefully things will get better. 
EDIT: Something I want to say is that there’s one thing you’ve got to consider: LingQ uses quite a bit of javascript. It’s the language which is so very powerful but becoming a bottleneck in browsers. Although, they have improved in that area in the last while. (But then people use it more hehe).
Yes, LingQ is now much slower than before.
You will experience the best performance if you use the Chrome browser from Google.
Well, there’s no guarantee of that, Hape. In my own checking to see which works faster, Firefox always came out on top over Chrome. Perhaps this is something to do with the length of the lessons I use, but in general it seemed to be slower in other sections of the site too. (In other words, it might be faster for some, but slower for others.)
JavaScript is a double edged sword. Yes its implemented differently in each browser, which causes many issues, but the reason it is so popular (and useful) is because it is executed on the client machine rather than the server. In many cases this is MUCH PREFERRED to forcing a round trip back to the server as well as putting all of the processing stress on the server. You want to see LingQ run as slow as molasses? Force it to do a complete page refresh every time you hover over a blue word. JavaScript isn’t perfect, and I’m sure there might be some areas where the programmers could refactor their code to improve its performance, but I doubt they could replace it with any technology to make it run any faster.
Yeah, the only way to avoid it would be to go completely out of the browser and make it an individual application with all the code running locally (could even be locally running js code for some components - technically possible but I guess it would be slower than good old c/c++).
(Not that I’m calling for this hehe).
I experience the same. Extreme slowness in all things. Especially today!
I have not seen any significant slowness since just after the upgrade.