The main goal is to have a Eclipse RCP-Widget to show an editor capable of editing HTML. On Windows 10 the Browser-Widget of RCP uses an embedded IE11 to render HTML, that's a given. Thus I needed some JavaScript based HTML-editor capable of running in IE11. After some research, because the Nebula RichText wont work with IE11 on Widows 10, I settled for Summernote (https://summernote.org/) with the bootstrap4-flavour and got it working.
Embedding resources in the Eclipse plugin is PITA and I was developing a client-server app anyways, so I've put the resources on the server. Thus the widget GETs all the fine stuff (css, fonts, js) from the server, like as it was running in a browser. Which by the way enables me to try different browsers with the hosted resources. Everything worked fine until we switched the client-server communication from http to https and the icons of summernote's toolbar went blank. Those icons are characters rendered with a special summernote font.
Using the IE11 browser (without the Eclipse RCP surrounding it) requesting the widget from the server I was able to find a difference between the http and https network traffic. On http the stylesheet requested just summernote.eot? as a font resource. On https there were two additional requests, one for summernote.tff?something and one for summernote.woff?something. Comparing the traffic with Chrome showed, that Chrome requested only the woff variant and rendered the icons correctly.
Why is IE11 requesting other font-encoding-variants when using https in comparison with http anyways? Can that be a cause for the icons to suddenly disappear?
