[KevinH]

These are "different" open with tools. The Preferred XHtml Editor is dedicated primarily to PageEdit but others can be placed there but it meant for the potential to edit multiple xhtml files in an epub by passing the address of the opf.

The standard BookBrowser pop-up menu "Open With" is meant for any single file editor. It exists by file type, so you can specify many different external editors specific to each file type.

PageEdit is not really placed there for xhtml files as it is more useful when launched via the preferred xhtml editor manner as it groks the OPF.

So right clicking on an xhtml in BookBrowser will not offer PageEdit, but instead a single file editor for the xhtml file type.

So different mechanisms.

The issues with regular "open with" only happen on Mac, not Linux because some Mac Apps have Multiple Main Window capabilities and can not be launched multiple times, and will not close when the last window is closed by the "x" in the title bar and must be Quit out of.

Linux does not use the multiple Main Window paradigm and so auto quits when the last window is closed and multiple instances of any program can be run.