Some people do not like the look and feel and the responsiveness of Swing apps. But actually what they do not like is not Swing, but it's default look and feel. In Java 5/6 SE days Swing is really fast and responsive.
Check out this post and especially the screencast how slick can it be. The bluemarine software is not only slick, but it even supports RAW format - so it's worth to install after the viewing the screencast :-).
Web Apps, SPA, PWA with vanilla Java Script (ES 6+), CSS 3 and WebStandards only. As simple as possible, but not simpler. See you at: (Progressive) Web apps, Single Page Apps and WebStandards airhacks workshops at MUC airport, Winter Edition
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