There seems to be a problem with the certificate of the website. The LingQ support has been informed by me via email.
I was not able to log in and the forum showed only the first post of the threads.
You can help yourself inbetween going to the browser settings and untick the OSCP-Server check box. At least this works with Firefox for me.
this worked for me too. you can find it here (in firefox): Tools => options => advanced
It also seems to have cured the problem with the vocabulary page. Prior to removing the OCSP check I had no dropdownlists for Dates or LingQ Quantity.
Removing the OCSP check is not a permanent fix, however. There is risk involved in not checking certs with OCSP. Especially if you do online banking or shopping, no?
This should defenitely be fixed as fast as possible. Iām not feeling well with this solution.
Weāve received lot of complaints about this. Iāve just reported it, and it should be hopefully fixed as soon as possible.
Very many thanks, Vera, do you know if we need to go back and change the tick after Alex has fixed the problem? Thank you so much.
I reported this problem previously (Problems With Site On Safari (Ssl Cert Related) - Languag...), and experienced it again not long after the most recent update. Although in both cases it seemed to resolve itself after a while.
Hi everyone,
there is currently an issue that is affecting everyone who tries to sign in or sign up using Firefox. We should have this issue fixed on Monday, in the meantime please use another browser such as Chrome or Safari to access the site. Thanks!
I can only log in from Safari on iPad (as mentioned in my email to you yesterday) or use the app. Neither explorer nor chrome logins from laptop work - so itās not just a Firefox issue. I would rather use laptop! Patienceā¦sigh 
I replace the tick the minute I am signed out.
The issue has now been resolved. Sorry everyone, we realize how disruptive these issues are. Thank you for your patience.
Sorry it hasnātā¦ I can get to the log in page now, but when I put in username & password, I see āentering Lingqā, but then it just loads login page again (on laptop). Using iPad to type this.
Thank you. The update works for me.
Okay, explorer doesnāt work, but chrome works on laptop. Yayyyyyy.
Thanks for fixing it! I use Firefox and since Sunday I can log in on LingQ again!
<<āI replace the tick the minute I am signed out.ā>>
@SanneT - many thanks for the answer, very grateful.
Are you still having these issues in Explorer? We are unable to recreate them.