Example. Call with 

context —mode=FR

- Uncomment the first commented lines. Compilation fails because mode FR is on so that works

But I get English anyway. Uncomment the second commented part and it fails, but it should not because mode=EN is not turned on.

%\startmode[FR]
%  \BLURBONE
%  \stopmode

\startnotallmodes[FR,RU]% english is the default
\enablemode[EN]
\stopnotallmodes

\startmode[EN]
%  \BLURBTWO
\setuplanguage[en][patterns={en}]
\setupexternalfigure[directory=../LMTX-Output/without-ids/en/ArchiMate 3.1 Metamodel ESv4]
\stopmode
\startmode[FR]
\setuplanguage[fr][patterns={en,fr}]
\setupexternalfigure[directory=../LMTX-Output/without-ids/fr/ArchiMate 3.1 Metamodel ESv4]
\stopmode
\startmode[RU]
\setuplanguage[ru][patterns={en,ru}]
\setupexternalfigure[directory=../LMTX-Output/without-ids/ru/ArchiMate 3.1 Metamodel ESv4]
\stopmode