Highlight all occurrences of pointed identifiers
Often users use standard browser search capabilities for highlighting all occurrences of pointed identifiers corresponding to, say, variable names. This is not convenient since several extra actions (copy, paste, select a highlighting option) are always required. I suggest to implement this feature for all identifiers of class SrcHlN (cross referenced identifiers that have specific connections will have other classes always).
At this point highlighting will not be semantic like at, say, https://code.woboq.org/linux/linux/net/core/dev.c.html#256str where exactly all occurrences of a given variable is shown since this needs corresponding knowledge from source code querying that is non-trivial to obtain.