Broken selection panel UI for (at least) custom data?

[teh-cmc]

If you look at the recording resulting from this thing:

rr.init("rerun_example_any_values_send_columns", spawn=True)

timestamps = np.arange(0, 64)

# Log two components, named "sin" and "cos", with the corresponding values
values = rr.AnyValues(
    sin=np.sin(timestamps / 10.0),
    cos=np.cos(timestamps / 10.0),
)

rr.send_columns(
    "/",
    times=[rr.TimeSequenceColumn("step", timestamps)],
    components=values.as_component_batches(),
)

what you'll see is that on 0.21 it shows what you'd expect:

whereas on latest main is not only doesn't show what you'd expect, what it shows is just plain wrong (that's the size of the whole column, not this specific value at this specific timestamp):