You may find it useful to manage the use of Adobe Flash within Safari.
Open Safari Preferences
Click the Security tab
Click Plug-in Settings
Click the Adobe Flash Player in the left column.
For each website that you’ve visited, that uses Flash, there’s an entry in this table. Each can be assigned one of three options.
There is also a setting for allowing other websites to access Flash.
Click Done when satisfied.
Note: You can set a default for websites not listed.