With the COVID-19 situation in Shanghai improving, suppliers of U.S. big techs have gradually begun to ramp up production to pre-COVID levels. Taiwan-based Quanta Computer, which manufactures about three-quarters of Apple, Inc.’s AAPL MacBooks, has resumed production at its Shanghai facilities, noted analyst Ming-Chi Kuo said. The analyst had previously noted that Quanta is the sole supplier of Apple’s high-end MacBook Pros. The company has eight factories in Shanghai, employing about 40,000 workers. Related Link: [Why This Apple Product Is Facing Tightest Supply Situation]( https://www.benzinga.com/analyst-ratings/analyst-color/22/05/27337205/this-apple-product-is-facing-tightest-supply-situation) Quanta also supplied components to electric vehicle giant Tesla, Inc. TSLA. Kuo, an analyst at...