The entry preview window does not load my customized visual theme

[crystalfp]

JabRef 5.2--2020-10-15--13a80ba
Windows 10 10.0 amd64
Java 14.0.2

• Mandatory: I have tested the latest development version from http://builds.jabref.org/master/ and the problem persists

The entry preview window does not load my customized visual theme as the rest of the GUI. I loaded my customized visual theme (copy of the source Dark.css file) but was not able to change colors of the preview textarea to match the dark theme of the rest of the GUI. Instead selecting "Dark theme" from Options > Appearance correctly makes the background dark.

Steps to reproduce the behavior:

1. From the source tree take the Dark.css file
2. Open Options > Appearance and select this file as "Custom theme"
3. Restart JabRef and double click on an entry. The preview textarea has a white background
4. If you select instead "Dark theme" the background is correctly dark.

I suspect the problem is in file: jabref-master\src\main\java\org\jabref\gui\preview\PreviewViewer.java where I don’t see any reference to theme in JS_HIGHLIGHT_FUNCTION definition or in setPreviewText() function, so the #previewBody block in Dark.css has no effect.

[Siedlerchr]

The file is right, but the highlight function is only used for highlighting search results in the preview.
The real problem lies here. Should be enough to modify the condition

jabref/src/main/java/org/jabref/gui/preview/PreviewViewer.java

Lines 119 to 129 in 6dec174

	public void setTheme(Theme theme) {
	if (theme.getType() == Theme.Type.DARK) {
	// We need to load the css file manually, due to a bug in the jdk
	// TODO: Remove this workaround as soon as https://github.com/openjdk/jfx/pull/22 is merged
	URL url = JabRefFrame.class.getResource(theme.getPath().getFileName().toString());
	String dataUrl = "data:text/css;charset=utf-8;base64," +
	Base64.getEncoder().encodeToString(StringUtil.getResourceFileAsString(url).getBytes());
	previewView.getEngine().setUserStyleSheetLocation(dataUrl);
	}
	}

[crystalfp]

Maybe simply adding a toggle "The custom theme is a dark theme" to pass the test if (theme.getType() == Theme.Type.DARK) { is sufficient.

[Siedlerchr]

I would just change the condition and replace it with != Theme.Type.LIGHT

[crystalfp]

Eagerly waiting for this change. Thanks!