Not all color changes are applied

[WouterVanNifterick]

Some color changes are not applied in the IDE after clicking "apply changes".

To reproduce the issue, do this:

1. Start the IDE colorizer
2. Go to the Theme Settings / Headers tab
3. Check "use custom colors for the headers"
4. Change "start color gradient"
5. Hit apply changes

The color doesn't get updated.

The only way to get the colors in that tab to update the IDE is to change the font color and hit apply, which causes both the font and the previously applied changes to aply.