With this release FDT can easily switched to dark theme:Simply select the Dark theme and apply. The Dark theme is available since Eclipse 4.4 (Luna). Older versions of Eclipse (and FDT) does not support color themes of this form.

The FDT views and editors will switch to their default dark color set:

In case you use a different third party color theme (plugin) you can manually set the default dark color for the editor here:

To switch the semantic highlighting to dark mode use this preferences:

The last part is the AsDoc:Then the AsDoc view will present its contents using the dark theme defaults.