Steps:
1. Create 2 free-style jobs with "Watch Job" enabled:
Test1 and Test2

(To enable "Watch Job" you need to add "Editable Email Notification" step in Post-Build)

2. Click "Watch Job" link to configure job watching for Test1 job
and "SUBMIT" and the link becomes "Configure Job Watching"

3. Open Test2 job and "Watch Job" link becomes "Configure Job Watching" too!

4. Under "User > Configure > Extended Email Job Watching" setcion,
it shows "No configuration available"
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At this point, only Test1 watch job email notification is really working
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5. Open Test2 job and click "Configure Job Watching" and "SUBMIT"
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Now both Test1 and Test2 watch job email notification is working.
But job wtach configuration in one job affects configurations in other jobs,
and "User > Configure > Extended Email Job Watching" setcion still shows "No configuration available".
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6. Open "Test1" job and stop job watching.
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This would stop all of job watching including "Test2".
"Test2" job link becomes "Watch Job" and no more emails
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