Hi! I understand that the speed control (the tortoise, rabbit, etc.) on the Windy.com weather radar loop has disappeared for you on your Mac running OS X 10.15. Let me help you get that back or find an alternative way to adjust the radar animation speed.

First, a couple of quick questions:
- Are you using Windy.com through a web browser or the Windy app?
- If it’s a browser, which one are you using? (Safari, Chrome, etc.)
- Have you noticed if this happened after a recent update or change?

Meanwhile, here are some general steps we can try:

1. Check the Radar Settings:
- On the Windy.com map, make sure you have selected the radar layer. Sometimes speed controls are tied to specific layers and might not appear if the wrong layer is selected or if the radar feature is not fully loaded.

2. Look for the Timeline Controls:
- The speed buttons (tortoise, rabbit, horse) used to be positioned near the timeline slider under the radar map. Can you see the timeline slider at all? Sometimes the speed presets are hidden behind small arrows or menu icons near the timeline. Try clicking or hovering around that area to uncover any hidden controls.

3. Clear Your Browser Cache and Restart:
- Cached data sometimes causes UI elements not to load correctly. In Safari, you can clear cache by going to Safari > Preferences > Privacy > Manage Website Data > Remove all, then restart the browser and reload Windy.com.

4. Try a Different Browser:
- If you are on Safari, try opening Windy.com in Chrome or Firefox to see if the controls appear there. This helps determine if the issue is browser-specific.

5. Update Your Browser:
- Since you're on OS X 10.15, make sure your browsers are updated to their latest versions supported by the OS. Old browser versions might have compatibility issues with Windy’s interactive features.

6. Check for Recent Updates on Windy.com:
- Occasionally, features or their UI change with updates. From the community discussions I found, some users have reported changes or issues with speed controls on radar loops recently. Sometimes, toggling between different time ranges on the radar animation (like 1h, 6h, 12h) affects these controls' visibility, so try switching those and see if the speed controls reappear.

If these steps don’t bring back the speed controls, please let me know what you’ve tried and I can help you dig deeper, possibly guiding you through browser developer tools or checking your account settings.

Are you satisfied with these first suggestions to start with?