MultiSelect freezes IE 11 on change

[decatur]

When changing the selection on a MultiSelect widget, IE11 dies.

from bokeh.plotting import curdoc
from bokeh.models.widgets import MultiSelect

def change_callback(attr, old, new):
    print(new)
    
select = MultiSelect(title='Select source', value=['a'], options=['a','b'])
select.on_change('value', change_callback)
curdoc().add_root(select)

Bug confirmed with Bokeh 0.12.4 and IE11.0.9600. change_callback handler is called once (['b'] is printed), then IE hangs. No problem with Select-Widget (single).
See also https://stackoverflow.com/questions/41839541/bokeh-multiselect. A related issue could be #5832.

[bryevdv]

@decatur can you test 0.12.5, and ideally with a 0.12.6 dev build? If there was an issue in the past its possible it has been fixed since and it is important to determine that as a first step. Dev builds are easily installable:

http://bokeh.pydata.org/en/latest/docs/installation.html#developer-builds

Can you verify this problem is limited to IE11 and not other browsers?

[bryevdv]

For reference I cannot reproduce any problem with either of those (or with 0.12.4) on OSX/Safari.

[blacknapkins]

I have tried the given example on Win 7 IE 11 with the same issue; a crash occurs after the ['b'] is printed. I used Bokeh 0.12.6dev6 and Python 3.5.3.
Chrome and Firefox do not display this erroneous behaviour.
The IE 11 JS console does not display any information prior to the crash occurring.

With IE 11 connected I get the following output every so often, which may or may not be connected.

Traceback (most recent call last):
File "C:\ProgramData\Anaconda3\envs\bok_0_12_6dev6\lib\site-packages\bokeh\ser
ver\views\ws.py", line 167, in on_pong
self.latest_pong = int(codecs.decode(data, 'utf-8'))
ValueError: invalid literal for int() with base 10: ''
2017-05-29 18:43:48,447 received invalid integer in pong b''

[bryevdv]

@blacknapkins thanks for the update. It's unfortunately probably too late to do anything about this for 0.12.6 but I have slated it for a look for the following release.

FYI AFAIK the message about the pong is annoying, but harmless. We've not been able to track down a solid repeatable test case for it but it never seems to interfere with expected behavior either.

[blacknapkins]

@bryevdv thanks for the info wrt the pong, I had a vague memory of seeing that somewhere but couldn't find it when I had a quick look.

[decatur]

Yes, we have the exact same symptoms as @blacknapkins observes. Because he did already test against the dev build, I will refrain (sitting behind a not so cooperative corporate firewall).
Btw, corporate policies often dictate the deployed browser, which also often is IE exclusively.