Zoom to fit isn't automatic when changing units in symbol editor

[KiCad bug report]

When double-clicking on a symbol-name in the library tree view on the left of the interface, the symbol systematically opens with an implicit zoom-to-fit. When the symbol is composed of multiple units, the zoom-to-fit is not implicitly applied when changing to another unit.
Has this been done with a special reason ?
If not, it might be good to connect the "zoom-to-fit" to the onchange-event of the unit-dropdown, the same way as with the onselect in the treeview.

Application: kicad
Version: (5.1.0-0), release build
Libraries:
    wxWidgets 3.0.4
    libcurl/7.54.0 LibreSSL/2.0.20 zlib/1.2.11 nghttp2/1.24.0
Platform: Mac OS X (Darwin 17.7.0 x86_64), 64 bit, Little endian, wxMac
Build Info:
    wxWidgets: 3.0.4 (UTF-8,STL containers,compatible with 2.8)
    Boost: 1.68.0
    OpenCASCADE Community Edition: 6.9.1
    Curl: 7.51.0
    Compiler: Clang 8.0.0 with C++ ABI 1002
Build settings:
    USE_WX_GRAPHICS_CONTEXT=ON
    USE_WX_OVERLAY=ON
    KICAD_SCRIPTING=ON
    KICAD_SCRIPTING_MODULES=ON
    KICAD_SCRIPTING_PYTHON3=OFF
    KICAD_SCRIPTING_WXPYTHON=ON
    KICAD_SCRIPTING_WXPYTHON_PHOENIX=OFF
    KICAD_SCRIPTING_ACTION_MENU=ON
    BUILD_GITHUB_PLUGIN=ON
    KICAD_USE_OCE=ON
    KICAD_USE_OCC=OFF
    KICAD_SPICE=ON

[Jeff Young (jeyjey)]

If you had a large symbol and were zoomed in on a particular area and needed to edit that area in multiple units, and auto-zoom-to-fit might be very annoying.

The question then becomes: on balance which is more useful: auto-zoom-to-fit or manual-only? I don't have a good feel for that....

[Michael Kavanagh (michaelkavanagh)]

Discussion on developer mailing list: https://lists.launchpad.net/kicad-developers/msg40038.html

[KiCad bug report (kicad-bug-report)]

@Jeff Young,

I agree that some discussion might be needed on whether to choose auto-zoom-to-fit or manual-only. However, now it is half auto-zoom-to-fit and half manual-only, which is probably the worst option...
You could also consider adding it as an option in the preferences, then everybody will be happy, and the functionality would be consistent for all cases.