The docs says the default format (numeral) uses a NumeralTickFormatter:
https://bokeh.pydata.org/en/latest/docs/user_guide/tools.html#formatting-tooltip-fields
And the NumeralTickFormatter accepts a language parameter:
https://bokeh.pydata.org/en/latest/docs/reference/models/formatters.html#bokeh.models.formatters.NumeralTickFormatter
But how to set the language of the numeral tooltip format?
Thanks for the attention.