Bonjour! I see you mentioned that the Matching Story app screen is black on your Mac running OS X 10.15.7. Let's get it fixed together.

Just to clarify first:
- Are you running the Matching Story app via a browser on your Mac or through some app player/emulator?
- When exactly does the screen go black—right at startup, after some gameplay, or randomly during play?
- Have you tried any steps so far like restarting the app or your Mac?

These details will help me guide you precisely. Meanwhile, a black screen issue in such games after updates is known and often related to graphic rendering hiccups or cached data conflicts.

Once you confirm, here are some general steps we can start with:

1. Restart the App and Mac:
Fully quit Matching Story (Cmd + Q) and relaunch. If no luck, reboot your Mac to clear temporary glitches.

2. Check for App Updates:
If you installed Matching Story through the App Store, check if there’s any update version available that may address this issue.

3. Clear Cache or Reset App Data:
Since this is on macOS, if it's a web app, clear your browser cache (Safari/Chrome). If it’s a native app, sometimes uninstalling and reinstalling fixes corrupted cache.

4. Compatibility with macOS 10.15.7:
Ensure the app version supports macOS Catalina (10.15.7). Sometimes after app updates, older OS support might break.

If it keeps showing a black screen after following these, do let me know what happens specifically. We can then look into more advanced options like permissions, graphic settings, or if there are known outages or bugs linked to the recent app update.

Are you ready to try these steps now? And please share a bit more about where and when the black screen appears.