jupyter python2 notebook may truncate in firefox

[DrXyzzy]

Reported on sage-cloud mailing list here, including zip file: https://groups.google.com/d/msg/sage-cloud/b8tgmK8gZ14/5eFs9HFaEQAJ

To reproduce:

• use firefox browser
• upload Skill4.zip into an SMC project and unzip
• in a .term, do wc -c Skill-04-ReadWriteFiles.ipynb; file length should be 20693
• open Skill-04-ReadWriteFiles.ipynb
  • you may see a warning like the screen capture below
  • notebook appears truncated; last cell displayed ends with paragraph
    __Using np.savetxt to Write Data Files ... __
• wait about a minute for the first jupyter auto-save
• in .term, again do wc -c Skill-04-ReadWriteFiles.ipynb and note file length is now 4202

Error seen on opening Skill-04-ReadWriteFiles.ipynb in firefox:

Workaround 1 - use Google Chrome at least once

• close jupyter notebook and restore Skill-04-ReadWriteFiles.ipynb by unzipping again
• open Skill-04-ReadWriteFiles.ipynb in chrome
• execute the first cell
• save the notebook
• close the SMC chrome browser tab
• in firefox session
  • note wc -c Skill-04-ReadWriteFiles.ipynb now gives length 13384
  • open jupyter notebook and observe it is no longer truncated

Workaround 2 - convert to .sagews:

• close jupyter notebook and restore Skill-04-ReadWriteFiles.ipynb by unzipping again
• convert to sagews with smc-ipynb2sagews Skill-04-ReadWriteFiles.ipynb
• open Skill-04-ReadWriteFiles.sagews and work with sagews

[williamstein]

Interesting: the fontSize is undefined error is the same thing that I fixed in #1343

[williamstein]

My latest commit seems to fix this -- it's just a worse hack...

[DrXyzzy]

Problem is still there for me. Firefox 50.1.0. OS X 10.11.6. I reset my dev project, refreshed Firefox SMC browser tab, and unzipped a fresh copy of Skill-04-ReadWriteFiles.ipynb.

Screen capture shows where the notebook is truncated as indicated by drop shadow below In [3]: display.

[DrXyzzy]

I see, the commit was reverted.

[williamstein]

NOTE: I've completely disabled Jupyter + firefox for now.

[DrXyzzy]

As with #1650, I'm marking this blocked until the next release of Firefox (after 51.0.1).

[DrXyzzy]

I just tested in Firefox 52.0, getting around the FF block on .ipynb by overriding the user agent setting. Bug is still there, i.e. opening the test notebook mentioned above in FF results in truncation - in fact it is even worse, in that none of the test notebook is visible on opening the file. Character count of Skill-04-ReadWriteFiles.ipynb goes from 14913 after unzip to 617 after attempting to open in FF. File opens without truncation in Safari.

[DrXyzzy]

process: reassigning to @williamstein because it looks as if this issue will unblock when some work in progress with Jupyter is completed.

[williamstein]

Closing this in favor of #1754, where Firefox will work perfectly.