Good morning, everyone, my colleague uses the same Eclipse that I do, the 2019-12 with Java 1.8 and we both have ZKStudios installed as plugins. I see everything correctly zuls with all the tags, while she sees a text page. It completely lacks the option to see the zuls. She has reinstalled ZkStudios several times but to no avail. I attach screens of what I see and what my colleague sees. Has anyone ever had a similar problem?
my coworker zul page, not correct

We tried to reinstall the plugin
New info, thanks to comments, My coworker has this error when she tries to install zk studios :
org.osgi.framework.BundleException: Could not resolve module: org.zkoss.eclipse.editor [731] Unresolved requirement: Require-Bundle: org.eclipse.wst.common.snippets -> Bundle-SymbolicName: org.eclipse.wst.common.snippets; bundle-version="1.2.500.v201811170421"; singleton:="true" org.eclipse.wst.common.snippets [428] Unresolved requirement: Require-Bundle: org.eclipse.gef; bundle-version="[3.10.0,6.0.0)" -> Bundle-SymbolicName: org.eclipse.gef; bundle-version="3.13.0.202211301913"; singleton:="true" org.eclipse.gef [498] Unresolved requirement: Require-Capability: osgi.ee; filter:="(&(osgi.ee=JavaSE)(version=11))" Unresolved requirement: Require-Bundle: org.eclipse.draw2d; bundle-version="[3.7.0,4.0.0)"; visibility:="reexport" -> Bundle-SymbolicName: org.eclipse.draw2d; bundle-version="3.12.0.202211301913" org.eclipse.draw2d [490] Unresolved requirement: Require-Capability: osgi.ee; filter:="(&(osgi.ee=JavaSE)(version=11))" Unresolved requirement: Require-Bundle: org.zkoss.eclipse.zks -> Bundle-SymbolicName: org.zkoss.eclipse.zks; bundle-version="2.0.5.v202202111348"; singleton:="true" org.zkoss.eclipse.zks [735] Unresolved requirement: Require-Bundle: org.eclipse.gef -> Bundle-SymbolicName: org.eclipse.gef; bundle-version="3.13.0.202211301913"; singleton:="true" Unresolved requirement: Require-Bundle: org.eclipse.gef -> Bundle-SymbolicName: org.eclipse.gef; bundle-version="3.13.0.202211301913"; singleton:="true"



According to your screenshot, you don't open a zul file with a zul editor: (check the icon)
The zul editor icon is:
You can open a zul with zul editor:
Check file type and editor association: