notebook gives blank page when start

[andrewsunst]

It used to work fine until I changed python to lower version today(3.7 to 3.6). The jupyter notebook keeps giving me blank page when started. I changed the version back and it doesn't help. No error in the terminal. The error in the browser are as follows:
Refused to execute script from '<URL>' because its MIME type ('text/plain') is not executable, and strict MIME type checking is enabled. VM26 tree:1 Refused to execute script from 'http://localhost:8888/static/components/es6-promise/promise.min.js?v=f004a16cb856e0ff11781d01ec5ca8fe' because its MIME type ('text/plain') is not executable, and strict MIME type checking is enabled. VM26 tree:1 Refused to execute script from 'http://localhost:8888/static/components/preact/index.js?v=00a2fac73c670ce39ac53d26640eb542' because its MIME type ('text/plain') is not executable, and strict MIME type checking is enabled. VM26 tree:1 Refused to execute script from 'http://localhost:8888/static/components/proptypes/index.js?v=c40890eb04df9811fcc4d47e53a29604' because its MIME type ('text/plain') is not executable, and strict MIME type checking is enabled. VM26 tree:1 Refused to execute script from 'http://localhost:8888/static/components/preact-compat/index.js?v=aea8f6660e54b18ace8d84a9b9654c1c' because its MIME type ('text/plain') is not executable, and strict MIME type checking is enabled. VM26 tree:1 Refused to execute script from 'http://localhost:8888/static/components/requirejs/require.js?v=951f856e81496aaeec2e71a1c2c0d51f' because its MIME type ('text/plain') is not executable, and strict MIME type checking is enabled. VM26 tree:1 Refused to execute script from 'http://localhost:8888/static/tree/js/main.min.js?v=ab9f3a6cf8347df927864d58cfad7931' because its MIME type ('text/plain') is not executable, and strict MIME type checking is enabled. VM26 tree:24 Uncaught ReferenceError: require is not defined at VM26 tree:24

I check some other posts which said to clean browser caches and cookies which doesn't help for my case. Any idea about how to fix this problem?

[joddiy]

Me too, with python3.7 at windows10.
And from the log, there's a 302 redirect record:
[I 01:04:46.632 NotebookApp] 302 GET /tree (::1) 1.00ms
I guess the localhost address is redirected to ::1.

[windyslove]

I have the same issue , python3.7 ,win10

[andrewsunst]

Me too, with python3.7 at windows10.
And from the log, there's a 302 redirect record:
[I 01:04:46.632 NotebookApp] 302 GET /tree (::1) 1.00ms
I guess the localhost address is redirected to ::1.

We have exactly the same problem in here.

Same issue here on Python 3.7.2, experienced on both Chrome (before and after clearing cache) and on Microsoft Edge. The issue appears to be that Jupyter's webserver is returning Content-Type: text/plain for main.min.js and all other JS files, which causes browsers to reject loading them under MIME checks.

Edit: It's most likely that this is an issue with the latest changelog item, which involves Content Type option changes:

5.7.6
-----

5.7.6 contains a security fix for a cross-site inclusion (XSSI) vulnerability,
where files at a known URL could be included in a page from an unauthorized website if the user is logged into a Jupyter server.
The fix involves setting the ``X-Content-Type-Options: nosniff``
header, and applying CSRF checks previously on all non-GET
API requests to GET requests to API endpoints and the /files/ endpoint.

The attacking page is able to access some contents of files when using Internet Explorer through script errors,
but this has not been demonstrated with other browsers.
A CVE has been requested for this vulnerability.

Edit 2: Opened a PR with a quick fix.

[andrewsunst]

@ciaranlangton Hey, thanks for the update but here is the strange thing. I tried the latest version (5.7.6) on another pc and it works fine. I also tried to modify the notebookapp.py as your pr but it doesn't fix the problem. So I am thinking about there might be something else.

@andrewsunst sorry to hear that it didn't fix it, is the other PC a Windows based machine? Plus, when you applied the patch, did you clear cache (either explicitly through browser options or CTRL+F5). It would also be helpful if you could see what the Content-Type header is on the working PC for the JavaScript files

[andrewsunst]

Well actually, it works after I clean the cache! So for the one that works, I don't exactlly know what do you suggest to take a look at. Is that something from the browser? If so then it is as follows:

You can check the Content-Type in Chrome by switching to the Network tab at the top of the debug console, and then refreshing the page (ideally with a CTRL F5). The files and requests will be visible in a list to the right, select any .js file from there, and then on the left there will be a pane containing a lot of information, under “Response Headers” you should see Content-Type: ......

[andrewsunst]

So I followed your procedure and found the content-type in only one of the .js files which is http://localhost:8888/static/tree/js/main.min.js?. The content-type appears as
E.setRequestHeader("Content-Type",h.contentType)
and I checked the value of it which I think is as follows
return utils.promising_ajax(this.api_url(), { processData: false, type : "PATCH", data: JSON.stringify(newdata), dataType : "json", contentType: 'application/json', }
The other one is contentType:"application/x-www-form-urlencoded; charset=UTF-8". So is there anything we can get from these?

[Ornstein89]

Still same problem. Blank page in either Chrome, or Opera. Either file tree page, or notebooks pages.
Got message in the console after attempt F5 or Ctrl+F5
[I 11:27:26.543 NotebookApp] 302 GET /?token=3023f5b77855d20b9cba73dd0036e2a7a4df1c1c77fcae77 (::1) 1.00ms
and

in browser.
Win10 1809 17763.348, latest Chrome 72.0.3626.121, python 3.7.1. By the way, downgrading jupyter and it's separate components, included ipython, with pip, make file tree page visible, but notebook page still blank.
P.S. ipython notebook shows the same behavior.

[simonsaysL]

I am having the same identical issue here. Both with python 3.6.8 and python 3.7.1. Browsers: Opera, Brave and Microsoft Edge

[xNi-cOx]

Same Problem here. Python 3.7.2 and Jupyter notebook 5.7.6. Tried Firefox, Chrome, Opera and Edge

[alvaroqueiroz]

I have the exact same problem, any solutions yet?

[TareqMonwer]

Same problem for me.
Downgraded notebook to 5.7.4, now it is working.
So do
pip uninstall notebook
pip install notebook==5.7.5
edit: use 5.7.5 instead of 5.7.4, see below

Worked for me as well :)

[apiszcz]

Had similar issue with 5.7.6, updated to 5.7.7 issue resolved

[swayson]

This issues seems to occur in 5.7.8 as well.

[swayson]

Update: Okay, it seems to be working again in 5.7.8. Had to clear my cache.

[BPietschSNI]

None of these fixes worked for me, but changing my default port to something besides 8888 worked. I do a lot of work on AWS where I tunnel into that port to use Jupyter notebook, so that must have had something to do with it. Even with that connection closed though, my local notebook on 8888 didn't want to load and I was getting the same errors as above.

[feldoh]

For me it was clearing the cache

[Ianwww]

running notebook in aws, after login i get a 302. help????????

[amdegroot]

@lanwww I am running into the same issue. Was running from an ec2 instance and port forwarding, and now I am running into this 302 issue on my Mac.

[amdegroot]

removing the config folder: ~/.jupyter/ solved it for me.

[Wildprogrammingape]

Same problem for me.
Downgraded notebook to 5.7.4, now it is working.
So do
pip uninstall notebook
pip install notebook==5.7.5
edit: use 5.7.5 instead of 5.7.4, see below

Good job man. It works!

[jainsanmati]

I also had the same problem. steps I followed. "conda install jupyterlab"
thats all, then it asked me for rebuild, did that and jupyter lab working fine.