Hi,
I’m not a native English speaker, and I’m unsure if here is a second to needed:
Blockers are alarms that set the state of the node they belong to to error.
LanguageTool 6.0 reports a possible mistake.
It’s okay. First to is of belong, second of verb.
LT is warning, not saying it is wrong. But it is a false positive, that could be prevented.