Mousewheel zoom in mapviewform example breaks the map

[chrismayer]

When zooming the map with the mousewheel as first action in the mapviewform example the map is broken afterwards (blank screen wo/ map tiles):

When the user performs a zoom action with another control, eg.g the +/- buttons in the top left corner or by the form first the mousewheel zoom will not break the map anymore.

This happens with OpenLayers v3.20.1 and with v4.3.2. Tested on the latest versions of Chrome, Chromium and FF on a Ubuntu 16.04 LTS. With OL v4.3.2 an error message is logged:

{message: "Assertion failed. See https://openlayers.org/en/v4.3.2/doc/errors/#32 for details.", 
code: 32, 
name: "AssertionError"}

with can be translated to

Transformation matrix cannot be inverted.

[chrismayer]

@bentrm would you mind have a look at this, since you developed this example? Would be very cool. TIA!

[bentrm]

Do you think this is a browser thing? I'm a bit perplexed as this example has been online with 3.20.1 a while now, or have there been changes I'm not aware of? Also in Safari, zooming via mouse wheel seems to work, but the zoom buttons are broken.

[chrismayer]

At all this is really strange.
As stated above this only occurs if the mousewheel zoom is the first zoom interaction at all (in the mentioned browsers). If Safari brings other strange behavior it might be really a browser thing.