Tickformat is not working as expected

I am trying to display milliseconds up to 3 fractional numbers using tickformat : ‘%H:%M:%S.%3f’
but is just displaying 1 fractional part.

That .%3f piece isn’t a valid time format.

I think https://codepen.io/etpinard/pen/NzgXJK?editors=0010 is what you’re looking for.

Thanks etienne for the help.
But I am looking to display up three fractional places like “23:42:46.302” but it is displaying like 23:42:000".
Can you please let me know how can we do that? Please find the documentation snapshot of tickformat.
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