In 2018, web developers faced challenges in ensuring compatibility of multimedia formats across various browsers, given the diverse range of codecs and formats available. WebM, Ogg Theora Vorbis, Ogg Opus, and MP4 were among the notable formats, each with varying degrees of browser support. For instance, while MP4 was widely supported, it was not royalty-free, making it less ideal for an open web platform. Animations also played a crucial role in enhancing web experiences, with technologies like CSS, HTML, and JavaScript offering advanced animation capabilities, replacing the outdated Flash format, which Adobe planned to retire by 2020. To maintain engaging and efficient websites, developers needed to be mindful of supporting formats and technologies, leveraging new web animation APIs for improved browser processing. Understanding and addressing compatibility issues with HTML5 and CSS3 were essential to optimize multimedia integration on websites during this period.