The most complete Eclipse plugin is still the one that was developed at JBoss Tools long ago, but it was discontinued 2 years ago. So, I have taken over basic maintenance in my Github fork (https://github.com/ddekany/jbosstools-freemarker), and published a new version on Eclipse Marketplace (https://marketplace.eclipse.org/content/freemarker-ide). Also, if you try to open an .ftl, .ftlh or .ftlx file in Eclipse, now Marketplace will find this plugin automatically.
Basic maintenance practically means replacing the embedded freemarker.jar with the latest version, and uploading to Bintray, and adding a new version on Eclipse Marketplace. Anyone, especially any PMC member with Bintray and Eclipse user, to who I can give right to editing these? Just so that releasing a new plugin version stays possible even if I'm not available. The biggest problem with this plugin is that it only recognizes FTL syntax, not the static text. Like in a HTML template you have no HTML syntax highlighting/completion. This limits the use cases. To address that, there's https://github.com/angelozerr/lsp4e-freemarker, but it has become inactive. Would be great if someone picks that up.
