BRUSSELS (Reuters) -Adobe's $20 billion bid for cloud-based designer platform Figma could reduce competition in global markets for interactive product design tools and also shut out rivals, EU antitrust regulators said on Monday. The European Commission said it opened a full-scale investigation into the deal after a preliminary review triggered concerns, confirming a Reuters story last month. Figma's web-based collaborative platform for designs and brainstorming is popular among tech companies including Zoom Video Communications, Airbnb and Coinbase.