I found a way to wrap everything before \= startdocument, so I think this looks like a template more or less:

In case anyone is interested, here's the MWE:

\definenote[address]
\setupnote[address][rule=3Doff,location= =3Dtext]

\setupnotation[footnote][numberconversion=3Dnumerals]
\definenote[putjustmark]
\setupnote[putjustmark][location=3Dnone]<= br>\setupnotation[putjustmark][numberconversion=3Dset 2]

\define= note[putjustnote][footnote]
\setupnote[putjustnote][textcommand=3D\gobbl= eoneargument]
\setupnotation[putjustnote][numberconversion=3Dset 2]
<= br>\newif\ifnoteintitle
\newtoks\titlefootnotes

\titlefootnotes\e= mptytoks

\def\thanks#1{\noteintitletrue\putjustmark{#1}\doglobal= \appendtoks \putjustnote{#1} \to \titlefootnotes}
\def\email#1{\noteinti= tletrue\putjustmark{#1}\doglobal\appendtoks \putjustnote{#1} \to \titlefoot= notes}

\def\unskipfunnylines{\ifnoteintitle\endgraf\kern-2\lineheigh= t\fi}

\definenamespace
=C2=A0 =C2=A0[addr]
=C2=A0 =C2=A0[t= ype=3Dmodule,
=C2=A0 =C2=A0 name=3Daddress,
=C2=A0 =C2=A0 command=3Dy= es,
=C2=A0 =C2=A0 setup=3Dlist,
=C2=A0 =C2=A0 parent=3Daddr,
=C2= =A0 ]

\define[1]\useaddress
=C2=A0 =C2=A0 {\setnotetext[address][= #1]{\namedaddressparameter{#1}{name}}}

\setupaddress[style= =3Ditalic]
\defineaddress[fst][name=3D{Name of Institute or Affiliation,= City, Country}]
\defineaddress[snd][name=3D{Name of Secondary Institute= or Affiliation, City, Country}]
\defineaddress[thd][name=3D{Name of Thi= rd Institute or Affiliation, City, Country}]

\processcommacommand[fs= t,snd,thd]\useaddress

\startsetups [document:start]
The T= itle\dorecurse{10}{\expanded{\thanks{Work supported by fund \recurselevel.}= }}
\endgraf

Me\dorecurse{10}{\expanded{\email{\tt my.name@mailbox= .\recurselevel.com}}\high{,}}\note[= address][fst]\high{,}\note[address][snd]\high{,}\note[address][thd]
\end= graf

\placenotes[address]

\blank[medium]
=C2=A0 \startcolu= mns\hyphenpenalty1000

=C2=A0 \the\titlefootnotes\relax

=C2=A0= \setcounter[footnote][0]

=C2=A0 \unskipfunnylines

\stopsetup= s

\startsetups [document:stop]
=C2=A0 \stopcolumns
\stopsetups=

\startdocument

test\footnote{test}

\input= knuth

\input knuth

\input knuth

\input knuth

\= stopdocument

On Wed, May 18, 2022 at 10:02 PM Ross <zhichu.chen@gmail.com> wrote:<= br>

After some visualisations, I found that my token \titlefootnotes will ALWA= YS generate two lines if there is/are any non-zero number of footnotes ther= e. Interesting. So I need a \newif that each time a \thanks or \email is in= voked, it'll set to true and I'll unskip the 2\lineheight afterward= s.

I still don't know why this \kern macro won't= have any effect if it's inside a token or a \startsetup.
On Wed, = May 18, 2022 at 4:56 PM Ross <zhichu.chen@gmail.com> wrote:
Hi Massi,

You are a champion!

On Wed, May 18, 2022 at 4:41 PM mf <massifr@fastwebnet= .it> wrote:
I hope I got the point now:

...
\startcolumns

\the\titlefootnotes

\kern-\rawcountervalue[address]\lineheight % dirty trick

test\footnote{test}

\input knuth

\stopcolumns
...

Massi

Il 18/05/22 10:07, Ross ha scritto:
> Dear Massi,
>
> Thanks for your solution. But the thing may be related to the
> \appendtoks macro. It doesn't work to put just \setnotetext there.=
> \note works fine, so that's the reason I need the "full funct= ional macro".
>
> Maybe I didn't get the point, so if it's not too much to ask, = could you
> do it on my MWE?
>
> PS: sorry I have to use another email account because my institute > mailbox took forever to get the message before my government (China) <= br> > finishes auditing it.
>
> Best wishes,
> Zhichu
>
> On Wed, May 18, 2022 at 3:36 PM mf via ntg-context <ntg-context@ntg.nl
> <mailto:ntg= -context@ntg.nl>> wrote:
>
>=C2=A0 =C2=A0 =C2=A0Is this what you mean?
>
>=C2=A0 =C2=A0 =C2=A0\starttext
>=C2=A0 =C2=A0 =C2=A0Hello\footnotetext{Footnote without mark}.
>=C2=A0 =C2=A0 =C2=A0\stoptext
>
>=C2=A0 =C2=A0 =C2=A0Kind regards,
>=C2=A0 =C2=A0 =C2=A0Massi
>
>=C2=A0 =C2=A0 =C2=A0Il 18/05/22 07:55, Zhichu Chen via ntg-context ha s= critto:
>=C2=A0 =C2=A0 =C2=A0 > Hi everybody,
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > After some attempts to put footnotes in a mix= ed 1&2 columns
>=C2=A0 =C2=A0 =C2=A0layout, I
>=C2=A0 =C2=A0 =C2=A0 > decide to put marks in the one-column environ= ment and flush them
>=C2=A0 =C2=A0 =C2=A0when
>=C2=A0 =C2=A0 =C2=A0 > entering the two-column environment.
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > The code is ugly but the result is acceptable= . Except that the
>=C2=A0 =C2=A0 =C2=A0invisible
>=C2=A0 =C2=A0 =C2=A0 > footnote marks do generate something in the m= ain text, so there's a
>=C2=A0 =C2=A0 =C2=A0 > blank line for each footnote.
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > Here's an MWE:
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > \definenote[address]
>=C2=A0 =C2=A0 =C2=A0 > \setupnote[address][rule=3Doff,location=3Dtex= t]
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > \definenote[putjustmark]
>=C2=A0 =C2=A0 =C2=A0 > \setupnote[putjustmark][location=3Dnone]
>=C2=A0 =C2=A0 =C2=A0 > \setupnotation[putjustmark][numberconversion= =3Dset 2]
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > \definenote[putjustnote]%[footnote] % if foot= notes need to be
>=C2=A0 =C2=A0 =C2=A0grouped,
>=C2=A0 =C2=A0 =C2=A0 > uncomment the second argument and the line af= ter \the\titlefootnotes
>=C2=A0 =C2=A0 =C2=A0 > \setupnote[putjustnote][textcommand=3D\gobble= oneargument]
>=C2=A0 =C2=A0 =C2=A0 > \setupnotation[putjustnote][numberconversion= =3Dset 2]
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > \newtoks\titlefootnotes
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > \def\thanks#1{\putjustmark{#1}\appendtoks \pu= tjustnote{#1} \to
>=C2=A0 =C2=A0 =C2=A0 > \titlefootnotes}
>=C2=A0 =C2=A0 =C2=A0 > \def\email#1{\putjustmark{#1}\appendtoks \put= justnote{#1} \to
>=C2=A0 =C2=A0 =C2=A0 > \titlefootnotes}
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > \appendtoks
>=C2=A0 =C2=A0 =C2=A0 >=C2=A0 =C2=A0 \setcounter[footnote][0] % this = looks stupid because it has no
>=C2=A0 =C2=A0 =C2=A0effect
>=C2=A0 =C2=A0 =C2=A0 >=C2=A0 =C2=A0 %\setupnotation[footnote][number= conversion=3Dnumerals]
>=C2=A0 =C2=A0 =C2=A0 > \to \titlefootnotes
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > \definenamespace
>=C2=A0 =C2=A0 =C2=A0 >=C2=A0 =C2=A0=C2=A0 [addr]
>=C2=A0 =C2=A0 =C2=A0 >=C2=A0 =C2=A0=C2=A0 [type=3Dmodule,
>=C2=A0 =C2=A0 =C2=A0 >=C2=A0 =C2=A0=C2=A0=C2=A0 name=3Daddress,
>=C2=A0 =C2=A0 =C2=A0 >=C2=A0 =C2=A0=C2=A0=C2=A0 command=3Dyes,
>=C2=A0 =C2=A0 =C2=A0 >=C2=A0 =C2=A0=C2=A0=C2=A0 setup=3Dlist,
>=C2=A0 =C2=A0 =C2=A0 >=C2=A0 =C2=A0=C2=A0=C2=A0 parent=3Daddr,
>=C2=A0 =C2=A0 =C2=A0 >=C2=A0 =C2=A0 ]
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > \define[1]\useaddress
>=C2=A0 =C2=A0 =C2=A0 >=C2=A0 =C2=A0=C2=A0=C2=A0 {\setnotetext[addres= s][#1]{\namedaddressparameter{#1}{name}}}
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > \starttext
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > \defineaddress[fst][name=3D{Name of Institute= or Affiliation, City,
>=C2=A0 =C2=A0 =C2=A0Country}]
>=C2=A0 =C2=A0 =C2=A0 > \defineaddress[snd][name=3D{Name of Secondary= Institute or
>=C2=A0 =C2=A0 =C2=A0Affiliation,
>=C2=A0 =C2=A0 =C2=A0 > City, Country}]
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > \processcommacommand[fst,snd]\useaddress
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > The Title\thanks{Work supported by somebody.}=
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0Me\email{myemail@some.where}\high{,}\note[address][= fst]\high{,}\note[address][snd]
>
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > \placenotes[address]
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > \blank[medium]
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > \startcolumns
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > \the\titlefootnotes
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > %\setcounter[footnote][0] % why it's nece= ssary to set the counter
>=C2=A0 =C2=A0 =C2=A0 > outside the token if I define [putjustnote] a= s [footnote]?
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > test\footnote{test}
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > \input knuth
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > \stopcolumns
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > \stoptext
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0___________________________________________________= ________________________________
>
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > If your question is of interest to others as = well, please add an
>=C2=A0 =C2=A0 =C2=A0entry
>=C2=A0 =C2=A0 =C2=A0 > to the Wiki!
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0 > maillist : ntg-context@ntg.nl <mailto:ntg-context@ntg.nl> /
>=C2=A0 =C2=A0 =C2=A0 > http://www.ntg.nl/mailma= n/listinfo/ntg-context
>=C2=A0 =C2=A0 =C2=A0<http://www.ntg.nl/mailman/= listinfo/ntg-context>
>=C2=A0 =C2=A0 =C2=A0 > webpage=C2=A0 : http://www.pragma-ade.nl &= lt;http://www.pragma-ade.nl> /
>=C2=A0 =C2=A0 =C2=A0http://context.aanhet.net <http://context.aa= nhet.net>
>=C2=A0 =C2=A0 =C2=A0 > archive=C2=A0 : https= ://bitbucket.org/phg/context-mirror/commits/
>=C2=A0 =C2=A0 =C2=A0<https://bitbucket.org/p= hg/context-mirror/commits/>
>=C2=A0 =C2=A0 =C2=A0 > wiki=C2=A0=C2=A0=C2=A0=C2=A0 : http://contextg= arden.net <http://contextgarden.net>
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0___________________________________________________= ________________________________
>
>=C2=A0 =C2=A0 =C2=A0 >
>=C2=A0 =C2=A0 =C2=A0___________________________________________________= ________________________________
>=C2=A0 =C2=A0 =C2=A0If your question is of interest to others as well, = please add an
>=C2=A0 =C2=A0 =C2=A0entry to the Wiki!
>
>=C2=A0 =C2=A0 =C2=A0maillist : ntg-context@ntg.nl <mailto:ntg-context@ntg.nl> /
>=C2=A0 =C2=A0 =C2=A0http://www.ntg.nl/mailman/list= info/ntg-context
>=C2=A0 =C2=A0 =C2=A0<http://www.ntg.nl/mailman/= listinfo/ntg-context>
>=C2=A0 =C2=A0 =C2=A0webpage=C2=A0 : http://www.pragma-ade.nl <http= ://www.pragma-ade.nl> /
>=C2=A0 =C2=A0 =C2=A0http://context.aanhet.net <http://context.aa= nhet.net>
>=C2=A0 =C2=A0 =C2=A0archive=C2=A0 : https://bit= bucket.org/phg/context-mirror/commits/
>=C2=A0 =C2=A0 =C2=A0<https://bitbucket.org/p= hg/context-mirror/commits/>
>=C2=A0 =C2=A0 =C2=A0wiki=C2=A0 =C2=A0 =C2=A0: http://contextgarden.net <http://contextgarden.net>
>=C2=A0 =C2=A0 =C2=A0___________________________________________________= ________________________________
>
>
>
> --
> Best Regards
> Chen

--
Best Regards
Chen

--
Best Regards
Chen

Best Regards
Chen