UserAgent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.108 Safari/537.36

Steps to reproduce the problem:
1. Run an Electron app that shows a system tray icon on Plasma 5
2. 
3. 

What is the expected behavior?
The system tray icon is properly rendered

What went wrong?
The system tray icon is cut off.

I traced it back to commit 9bf1973b0fe56de26cf85009457c9ed8f5e757d7 which tries to work around blurry icon rendering on Plasma 4. The system tray implementation in Plasma 5 is vastly different and enforces specific icon sizes and shouldn't exhibit this behavior as badly. Even if it did, there is an issue with the code:

chromium/src/chrome/browser/ui/libgtkui/app_indicator_icon.h

  // If |bitmap| is not 24x24, KDE does some really ugly resizing. Pad |bitmap|
  // with transparent pixels to make it 24x24.
  const int kDesiredSize = 24;
  SkBitmap scaled_bitmap;
[...]
  SkCanvas canvas(scaled_bitmap);
  canvas.drawBitmap(bitmap, (kDesiredSize - bitmap.width()) / 2,
                    (kDesiredSize - bitmap.height()) / 2);

When the bitmap provided to the function is larger than 24x24 px which seems to be the case usually, the icon is rendered out of bounds (e.g. a 48x48 icon will be rendered at coordinates -12,-12) and you can only see the center 24x24px of the icon.

Did this work before? N/A 

Chrome version: 63.0.3239.108  Channel: n/a
OS Version: 
Flash Version: 

Downstream KDE bug report https://bugs.kde.org/show_bug.cgi?id=366062