Thanks Ihor for your quick response.

I can confirm that in org 9.7.6 the behaviour for the font "Ubuntu" is the
expected one.

On Sat, 29 Jun 2024 at 08:34, Ihor Radchenko <yantar92@posteo.net> wrote:

> Giovanni Pavolini <giovanni.pavolini@gmail.com> writes:
>
> > I wanted to customize my default font by `(custom-set-faces '(default
> > ((t(:family "Ubuntu")))))`. Then, after `M-x org-table-create` the TAB
> > started creating a cell to the left of the one it should have jumped to
> > (see a video here (webmd video of the screencast):
> >
> https://u.pcloud.link/publink/show?code=XZVXhe0Z2K8AAQBKOwQH7uE7LkNtHYGlHQTy
> > ). The expected behaviour is that TAB only jumps to the next cell,
> > without creating additional ones. The actual behaviour is, depending on
> > the family font used, it does create an additional cell. Not every
> > font causes the unexpected behaviour.
>
> [ Side note: we prefer text descriptions on the mailing lists. Videos,
>   especially uploaded to third-party servers, may disappear after
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>
> From the video the reproducer is the following:
>
> 1. emacs -q
> 2. Create a new Org file
> 3. M-x org-table-create <RET> 2x2 <RET>
> 4. a TAB table TAB a TAB table
> 5. Observe table filled with "a" and "table" cells
>
> | a | table |
> |---+-------|
> | a | table |
>
> 6. M-: (custom-set-faces '(default ((t (:family "Noto Sans CJK HK")))))
> 7. Move point to the end of buffer
> 8. Repeat steps 3-4
> 9. Observe
>
> | a |   | table |
> |---+---+------|
> |   | a | table |
>
> I was able to reproduce using Org mode version shipped with Emacs 29.
> I was unable to reproduce using the latest Org mode version.
>
> May you please try to upgrade Org mode? Does the problem disappear then?
>
> P.S.
> Attaching the list of working/non-working fonts to keep it available for
> future reference.
>
>
> --
> Ihor Radchenko // yantar92,
> Org mode contributor,
> Learn more about Org mode at <https://orgmode.org/>.
> Support Org development at <https://liberapay.com/org-mode>,
> or support my work at <https://liberapay.com/yantar92>
>