Was able to successfully log in via a web browser (Opera).
Tried the clear data: no effect.
Tried the change to beta: same white window as reported by Merssedes Kurotsuki after entering credentials, so unsuccessful log in. Haven’t tried a roll back.
Mac OSX 10.13.6.

Mac OSX 10.13.6 (17G65) here.
Launcher logins broken as described here in thread. Web logins fine.
Caches cleared, I even deleted the CCP directory and reinstalled the launcher.
Eve Launcher Version 1225328
On macOS with the beta launcher, I get a white window immediately after clicking “login with EVE” from the launcher, but I noticed that if I resize the white window, it shows me a login page like what you see on the web site. If I log in there, it goes to another white screen (probably the same one @Merssedes_Kurotsuki reported) and resizing doesn’t do anything on that one. Right-clicking offers a “back” pop-up option that takes me back to the username/password screen, and a “reload” button with no apparent effect.
Login works fine for me in a web browser (Safari).
There’s a button on the page that first pops up to log in with Steam/Facebook which might be interesting to try for someone who has an account that way, but no use to me.
I tried the dev channel in launcher prefs (instead of beta) and that just straight up crashed immediately, and I tried deleting the Default dir in the Library as suggested, with no apparent effect.
Playing with an account previously added to the launcher worked fine, but wasn’t the account I wanted to play.
Note if anyone else is trying this on Mac (@Kelchu_Bizkack) you switch to the beta channel from the EVE Launcher>>Preferences… menu dialog (there’s no “E” menu).
I am having the exact same things as described by @Konith.
On a Macbook Pro, OS X 10.13.6
Unable to log in from the launcher. I’ve verified the integrity of files, deleted the launcher and reinstalled it, tried beta and dev versions…nothing works.
Tried with beta, also getting the resizable window, and the subsequent second white box. Unsuccessful login still, problems identical to @Konith. Mac OSX 10.11.
With the beta login, I can confirm that resizing the first white window then gives me a login page; previously, I hadn’t tried resizing, so I only got as far as the first white window. I then also get a second white window, behaviour the same as reported by @Konith.
I am having the exact same issue on my mac. It refuses to log in. Saying I need to check my internet connectivity. However, on my other two laptops (windows) they get the same error message but log in anyway.
Just adding my voice to the list of MacOS users unable to login with the above issues
Holy Crap I got it to work using Avalon’s method (both steps 1 & 2) using the beta launcher with one exception.
Fixed.
Let your damn launcher update to version 1376509.
hope that works.
Mine is at version 1243388. How do I get it at version 1376509?
http://binaries.eveonline.com/EveLauncher-1376509.dmg
did not work for me.
edit: I installed it again and its working now. weird
IM having the same issue, cannot see where 1376509 is. I only see 1243388.
Ive tried what Avalon suggested a dozen times, it never worked. And I never saw the “update UI” option.
Closest I came to logging in is opening the server list and directly connecting, but CCP disabled logging in via the app itself. This is so stupid its mind blowing.
Same issue here.
OSX 10.13.6
I see the SSO iframe errors in the logs.
Launcher shows version 1225328.3024
I don’t see any “beta” option anywhere.
I downgraded to the 1376509 launcher, and cancelled the automatic update download, and was able to log in.
I did the same as @Dice_Utama , and was also able to login.
Gah, this was infuriating. Hope this issue gets fixed soon.
Im in the process of doing the same thing as @Dice_Utama. However its downloading some massive 8.62GB file.
I’m not able to run the 1376509 launcher on Mac OS X. Here is the error : Dyld Error Message:
Library not loaded: /System/Library/Frameworks/CoreImage.framework/Versions/A/CoreImage
Referenced from: /Applications/EVE Launcher.app/Contents/Frameworks/QtWebEngineCore.framework/Versions/5/QtWebEngineCore
Reason: image not found
Finally logged with version 1376509. Before I installed version 1376509 I went back to the “release” version and not the “beta”. After that I installed the 1376509 version. I tried logging in and it accepted the connection. Now I’m connected.
This is incredibly frustrating. Fix this soon.
@Jeancun_Lobo I was just about to post that. 
Confirmed, the key is to go back and select “release”. From the 1376509 version. Be sure to press “cancel” after starting up the launcher, you don’t want to overright 1376509 launcher.