Presenter console does not work in Chromium-based browsers

[aumouvantsillage]

Based on a comment by @ejvindh in issue #211

Thanks for your new work on this issue in 19.11. I've done some tests on it, and it seems to me that it works best in Firefox (I didn't manage to have the views change in Chromium...). However -- personally I still miss the ability to resize the views :)

The following results are nested: (1) indicate tests in Chromium-based browsers; (2) indicate Firefox:

*** Summary of your problem or feature request**
Testing the presenterConsole in pre-release: 19.11

*** Version of Sozi and other relevant software**
Sozi-19.11.23-1574531954-linux-x64.tar.xz
xbuntu 18.04.3 LTS

(1) Brave Version 1.1.23 Chromium: 79.0.3945.88 (Official Build) (64-bit). Also tested on other Chromiumbased browsers like Chrome (70.0.3538.77 (Officiel version) (64-bit)) and Iron (66.0.3450.0 (Udviklerversion) custom (64-bit))

(2) Firefox 71.0 (64-bit)

*** Steps to reproduce the problem**
http://uploads.ejvindh.net/sozi1911_test.zip

*** Expected behavior**
(1) That views will change during playback of the presentation. To be able to change the sizes of the views.
(2) To be able to resize views of presenternotes and presented windows

*** Observed behavior**
(1) No changes in the presenterwindow. However the playback/-forward buttons seem to work.
(2) Cannot resize windows

*** Hints and solutions**
(1) Fun-fact: The views of the previous-current-next-window all show the first view of the presentation. However, it is possible to click upon the slide-number at the top-left corner and change each of the the views manually.