@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/vlbbji905dttaori-g5ys1wrcgqdvc... to http://www.plantuml.com/plantuml/png/~1vlbbji905dttaori-g5ys1wrcgqdvc... 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: vlbbji905dttaori-g5ys1wrcgqdvc7gzz99rkaxxr2314mnk8ax45mowr5ow6aqaahucquvv-6qfqkb zqkvhtflfvscmkh4m1x-uaqdez3oug6groec5o4eulrohoayh5ghfjqowvjhcmpipxoxwr1zmd6g9x82 sygi29qgq1ipgd_hepc7e0hyfbmdawjpk0ob0d8daa06r1wbskdi4z6xb1555ama12353n7nnuxqybuw q2eylgi978kask4t6t25hna1pjihgho0laxinm5t6ibrpaem98emexgh9uscmcp66tvpgwb-ipklhwga 8educjhyknsjc2w84s-ijblgehzhge-txmurs-vpbzxttct2xa-poclxaoahxunpju8ydm_35mrzxhnq l3szrtcx-nvulgmbes41d66l7em9tci-0sam0ql9iwu9q_9vyix7pkblmhtlflyox9no01rs1qp-0rz6 dxqr1ljwtrwpune6s-lno1_omiz35fo0kcqjrihbb-hbawz5ilu1 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