@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/vlbdji904bxp51lkl00nn8oq68d6dc... to http://www.plantuml.com/plantuml/png/~1vlbdji904bxp51lkl00nn8oq68d6dc... 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: vlbdji904bxp51lkl00nn8oq68d6dc1flzcajcixbu462pwue11397wo6ek39or6hgdnprfjugktbis5 44yxfzytcz_ckamb1dp1zwhnoffcbyt2jl9m815pl-dqbp8k5dmpmyxlb02d-kv7qn-tc37apa105gao af8fbf7accdcvbaudglg1kctj1kiywlsxj85shd8kgtmzombtgb9w52hal4a2p6gh88gbvwbgclwf0kj b66rakbno3olnf46l_yq2-26zwxt4mitreczn0ah7giewighbbizygptbbdddmet3vjibryvgymw3_ri aw76ajtlcgplhow8fuv3efe6zxvwnj1xq36xwj-tslt7nqxtxjc-u3nqkxyudjnvm99dzcqqfmjeleqc c-puydjz1qjulxmats8uxbxdmak7eosxux-4rwk0o_qbmyhfwrp8ha4tvnncrvkcmq4sjd8i7wuqnduu -eonwzs7gw_qnmyvymojvyvanzfrm96ez8ysogrsmdfea3xiafgs-wy0 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