Go to FF options. Privacy. Clear History When Firefox Closes. Click Settings. Then click all the options. You can leave Cookies and Active Logins. Close FF. Restart it. Check again. The asm.js window should not be there now as a pop up. Also, when you load up a game and then close the window, it should actually close and go away now. I am also running FF 33 recently released. That may have fixed it after clearing things out. Yes, it did do this to me also.

I installed Firefox 33 just now and I still get the white asm window blocking me from accessing my games, its really grinding my gears.
Nothing is blocking Javascript.

Thanks for the heads up Rassilon.750.

I have the latest Chrome version and when I go into My Library I have a "Humble asm.js Games" blank pop-up that won't go away...

Any way to make it dissapear? It's annoying as hell that I have to use IE...

My response from Humble Support about this.

"Hi there,

Thanks for reaching out to Humble Bundle Support!
I'm so sorry to hear that you are experiencing problems with the ASM.JS in-browser content!

We have noted an issue with the ASM.JS pop-up occasionally blocking the downloads on the download page and the Humble Library access, and are working to get both of those sorted as fast as possible! Currently, the best workaround is to utilize an alternate browser to access your content.

If you have any additional details surrounding the issue being experienced, we will happily pass those off directly to an engineer to be diagnosed. Any information on your browser, operating system, or the steps taken in reaching the error will be tremendously helpful!

Thanks for your cooperation and patience during our investigation!
Looking forward to hearing back!

Warmest regards,
Angel
Humble Bundle Support"

Yup, also got the white and empty asm.js window, which you can't close. I use NoScript and block everything except humblebundle.com, but also allowing all scripts on the page the window opens directly after everything is loaded and you can't close it. With using Comodo Dragon (based on Chromium) I have no problems.

Beside this problem, I really wish HumbleBundle could make a better library page. It's nice to get a list all games at once, but it would be really better to have a smaller start page with only the bundle list and the option to show the complete library.

It's only appeared for me in the last week.
I wonder what changed. :(

Well, yes, except for the occasional bugs of receiving free games from a sale, having your username changed, games disappearing from account. No, before you burn me at the stake, I understand these were all just random glitches, but GOG is very idolized in the eyes of many. Yes, I love it, but everyone has their problems.
*Hides under a rock*

same problem for me. fixed by temporarily disabling DoNotTrackMe and reloading the page. it's only a work-around, but it got the job done

I just an email from Humble Support about the asm.js popup problem.

"It appears that this problem is caused by the browser's zoom option being set to anything other than the default zoom. Our engineers are hard at work developing a fix for this problem so we should have a resolution deployed soon! :D

In the mean time, I recommend resetting the zoom option in the browser you are using so that you can successfully access your Humble Library. The zoom option should be found under the 'View' menu in your browser. Once you have successfully accessed your library you can reset the zoom option to its previous value.

I apologize for the inconvenience this issue has caused! Hopefully we'll have your Humble Library back to normal in not too long. Let me know if you have any further questions or concerns. Otherwise, take care and happy gaming!"

[Bold emphasis my own.]

So. although I've never monkeyed around with the zoom level in Firefox, I dutifully clicked on "Reset".
No difference whatsoever on my screen, but when I did log onto Humble, and it took me to "My Library", hallelujah! No popup!

Hope this helps other people.

Thanks, that fixed the problem.

You can also reset the zoom by pressing ctrl+0. In my case it doesn't help, maybe because I manually changed the dpi settings of firefox to get a bigger gui (in windows I use 125%, but a few months ago firefox changed it's behaviour to use it's only scaling at the usual 100%). Funny thing is that a few days ago it worked perfectly, so they must have changed something in the last few days again.

Edit: After playing around with different zoom levels and heavily reloading my library I got an email from humbles that someone is trying to access my account (what a surprise). I already downloaded my games via the Comodo Dragon browser, but it's really annoying that I can't access Humble Bundle via my portable Firefox browser I use for all my gaming stuff. I really hope they can fix it as soon as possible, better would be if they would made a cleaner library without loading everything at once.


Edit: Kind of funny, these online games were part of that firefox bundle. And the only browser who has problems now because of them is firefox.

My zoom was also set at 100% (the default) but I went back to the page, zoomed in and out a bit, then hit reset to default, reloaded the page and the pop-up was gone. My browser is Chrome. This works for me! Thanks Getcomposted.

I think hitting Crtl-0 would only cause an action if the level was not set at 100%. Perhaps that explains why this hasn't helped others.