Worked on the google/mozc repository to improve the reliability of input method handling, focusing on the IBus preedit state during language switches. Addressed a bug where deleted characters could reappear by ensuring the preedit string is cleared when no preedit text is present, which reduced visual glitches and enhanced the user experience for multilingual input on Linux. The solution involved targeted updates to the PreeditHandler, emphasizing stability and a clean user interface. Utilized C++ and applied expertise in Input Method Editor development and software engineering to deliver a robust fix, prioritizing stability over new feature development during this period.