>This is really old, but covers using the Web Browser control in VFP:
>http://west-wind.com/presentations/shellapi/shellapi.asp

Editor from this article works. FoxyPreviewer editor (atoutfox editor with buttons, language and other changes) uses same technique
but contains much more edit buttons. So I should use it instead of your editor sample.

Other way would be to run tinyMCE or similar javascript html editor but I'm not sore is this reasonable since
foxpro buttons can used to control editor.

FoxyPreviewer web browser download complete events contains

This.Document.Body.contentEditable = .T. && This is a good context menu

which caues exception

Member DOCUMENT does not evaluate to an object.

Also its init method contains

LOCAL lnLoadTimeout
lnLoadTimeout = 3       && seconds
WITH This.OBJECT
    .Navigate("about:blank")
    * Wait for load completion
    lnStartSeconds = SECONDS()
    DO WHILE .ReadyState # 4 ;
            AND (SECONDS()-lnStartSeconds <= lnLoadTimeout )
        DOEVENTS
    ENDDO
ENDWITH

Same loop is also used after loading file for editing.

This causes application to hang on runtime.

How to fix those issues ?

comment in its init method recommends to use one sys() function and _autoyield. Maybe this can used to fix.