Wild swings in Korea’s stock market this week triggered technical glitches at several brokerage trading apps, briefly showing incorrect balances and sending screenshots of unexpected windfalls viral among retail investors Friday. The week of volatility followed sharp market moves, driven by the U.S. and Israel-Iran war. After plunging earlier in the week, the benchmark KOSPI rebounded sharply Thursday. It rose more than 12 percent intraday, triggering buy-side sidecars within minutes of the market opening. According to industry officials, the mobile trading system of Korea Investment & Securities displayed incorrect balance information for some retirement pension accounts shortly after the market opened Friday. In certain cases, the number of shares and returns shown in the app differed from the actual holdings. The glitch quickly drew attention online. Screenshots circulating on an online stock community showed brokerage accounts with an evaluation amount of about 530 million won ($400,000), along with comments such as, “This isn’t my account — whose account is it?” and “For a