Bug description

When exporting a dashboard with a high number of charts (e.g., 33 charts) as a PDF or PNG, the exported file does not include all charts. In one example, only the first 24 charts are visible in the downloaded file, and the last visible chart is partially cut off. In another attempt, not all the charts appear in the export but no partial charts are showing.

Repro steps:

1. Make sure the following feature flags are on: DASHBOARD_VIRTUALIZATION, ENABLE_DASHBOARD_SCREENSHOT_ENDPOINTS, ENABLE_DASHBOARD_DOWNLOAD_WEBDRIVER_SCREENSHOT
2. Open a dashboard with a large number of charts (e.g., 33 charts, predominantly table and pivot table charts).
3. Make most of the tables full width and ensure the dashboard layout requires scrolling to see the charts
4. Export the dashboard as a PDF or PNG

Expected: The exported file should include all charts present in the dashboard, fully visible and not cut off.
Current: Export doesn't contain all charts or has cut off charts.

Screenshots/recordings

No response

Superset version

master / latest-dev

Python version

3.9

Node version

16

Browser

Chrome

Additional context

No response

Checklist

• I have searched Superset docs and Slack and didn't find a solution to my problem.
• I have searched the GitHub issue tracker and didn't find a similar bug report.
• I have checked Superset's logs for errors and if I found a relevant Python stacktrace, I included it here as text in the "additional context" section.