@startuml legend The plugin you are using seems to generated a bad URL. This URL does not look like DEFLATE data. It looks like your plugin is using HUFFMAN encoding. This means you have now to add an header ~1 to your data. For example, you have to change: http://www.plantuml.com/plantuml/png/xpbhiw9158rlzoa6xtq12m-ywwyjv8... to http://www.plantuml.com/plantuml/png/~1xpbhiw9158rlzoa6xtq12m-ywwyjv8... It will work this way You may contact the PlantUML team at plantuml@gmail.com But you should also probably contact the plugin authors you are currently using and send them this image For the record, here is your data: xpbhiw9158rlzoa6xtq12m-ywwyjv89ntxa1rktcnnnl2yo4sfd2axcakiwkj2ie3b5unbdnjsxsrvtt 5rehehp-_vzlpxc6cow0q_vqd3tmbfreqz0yah98jtd4dg1ajdv-vdstyqxbujzt-tnuw8xy_doba51b x8akygo63qgxtfytflzra0mw2miekeqkohmnes50qwyol8mrnprkzoewsyo6eqjn4vldr6invqf5p7bk ukeihcliumebribw69say5fohrvc3ji2lsa8kjajybgy0blyyxynhdbp42a3wzdu8vcdx_fxuz2co1_2 by-blt1biezvv4cjhxmyxlr2uug0fp97vb9am83xewdx5xvd-vgb8gmvg4wvqcgrlcorf4dqzmk7ejwy dg-upkcthkdhi29q6sz7bmczenqupkudqjh09jjqkilxhy9qxsqa7v7_m6qrbrzqjvjtu_-pwct9hgkc ri-v-vovezw0s7enbzj-0w00 endlegend @enduml Submit amiga aws-orange black-knight bluegray blueprint cerulean-outline cerulean crt-amber crt-green cyborg-outline cyborg hacker lightgray mars materia-outline materia metal mimeograph minty plain reddress-darkblue reddress-darkgreen reddress-darkorange reddress-darkred reddress-lightblue reddress-lightgreen reddress-lightorange reddress-lightred sandstone silver sketchy-outline sketchy spacelab spacelab-white superhero-outline superhero toy united vibrant       🎉 Discover the future PlantUML Web Editor! 🚀  PNG  SVG  ASCII Art