- Have a single firm (Firm1) selling a specific product P1
- Distribute P1 in your firms.
- Build a second firm ( Firm2) selling the same product P1
- let the game run for a while so that Firm2 has got some product P1 in its sales unit
- Pause the game
- while in pause; Destroy Firm1
- while in pause; With a P1 Sales Unit on Firm2 click on the "resupply broken links" button
[Edit] As of 4.4.18, this issue is no more.