Hover tooltip works incorrectly in scatter WebGL

In the code example below (using the scattergl) when the cursor is rolled over the bubble, the hover tooltip does not appear until the cursor is close to the center of the bubble. The tooltip itself also points to the center of the bubble.

This is different from the expected behavior observed with the regular scatter where the tooltip appears in relation to the boundary of the bubble, rather than its center. And the tooltip points to the boundary as well.

For the Plotly Express px.scatter, one needs to set render_mode='svg' to switch out of WebGL for the correct behaviour.

This results in an incorrect tooltip in WebGL appearing when the cursor is over the larger bubble in an example such as this one:

import pandas as pd
import plotly.graph_objects as go

df = pd.DataFrame({'x': [1], 'y': [1],'z': [100]})

fig = go.Figure()

fig.add_scattergl(
    x=df['x'],
    y=df['y'],
    marker_size=df['z'],
    mode='markers',
    marker_sizeref=0.01,
    marker_sizemode='area',
    showlegend=True,
    hovertemplate=(
        'x: %{x:.2f}<br>'
        'y: %{y:.2f}<br>'
        '<extra></extra>'
    ),
)

fig.show()

まず、提供されている go.Figure.add_scattergl を使った Python の例を実行し、その hover の挙動を通常の scatter と比較します。scattergl のエントリーポイントから WebGL の hover 処理を追跡し、期待される境界ベースのツールチップの挙動と render_mode='svg' との比較を参照します。大きなバブルが表示領域全体で反応し、ツールチップが境界を指すようになれば完了です。