An hlx2 file extension is related to the Apple DocViewer a document viewing app for Mac System 6.
HLX2 file extension - Apple DocViewer data
What is hlx2 file? How to open hlx2 files?
File type specification:
The hlx2 file extension is associated with the Apple DocViewer, a document viewing software for System 6.0.5 available for first family of Macintosh computers.
The hlx2 file contains various data used by the DocViewer.
Apple DocViewer is obsolete software.
This hlx2 file type entry was marked as obsolete and no longer supported file format.
This type of file is no longer actively used and is most likely obsolete. This is typically the case for system files in old operating systems, file types from long discontinued software, or previous versions of certain file types (like documents, projects etc.) that were replaced in higher versions of their original programs.