When creating a Ops Board, and an Alarm Details panel is added, all the text is shown on green.
I figured that the color is defined inside ".dashboard .wallboard-board", and that CSS style lives inside /opennms/VAADIN/themes/dashboard/styles.css, which is a file that exist at runtime. It doesn't physically exist under the servlet container. This is because the Ops Board is a Vaadin app, and the styles are defined on a file inside an OSGi bundled JAR.
Fixing this requires code changes.