Does this issue occur when all extensions are disabled?: Yes

• VS Code Version: 1.59.0
• OS Version: Windows 10

Steps to Reproduce:

1. Open three editor tabs: 1x source, 2x terminal
2. Click on editor tab headers to change tabs
   1. Source
   2. Terminal 2
   3. Source
   4. Wait a minute
   5. Terminal 1
   6. Terminal 2
3. Notice how content of the Terminal 2 appears in Terminal 1

Video reproduction: https://youtu.be/j2tWKjEtOjk

Additional notes

• Happens on both Stable and Insiders versions
• Does not happen 100% of the time; but still happens fairly often (about every 5 minutes)
• Workaround: switch terminal tabs again