diff --git a/UI/Base/LeftIndex.ts b/UI/Base/LeftIndex.ts
deleted file mode 100644
index 989483ffc7..0000000000
--- a/UI/Base/LeftIndex.ts
+++ /dev/null
@@ -1,25 +0,0 @@
-import BaseUIElement from "../BaseUIElement"
-import Combine from "./Combine"
-import BackToIndex from "../BigComponents/BackToIndex"
-
-export default class LeftIndex extends Combine {
-    constructor(
-        leftContents: BaseUIElement[],
-        mainContent: BaseUIElement,
-        options?: {
-            hideBackButton: false | boolean
-        }
-    ) {
-        let back: BaseUIElement = undefined
-        if (options?.hideBackButton ?? true) {
-            back = new BackToIndex()
-        }
-        super([
-            new Combine([new Combine([back, ...leftContents]).SetClass("sticky top-4")]).SetClass(
-                "ml-4 block w-full md:w-2/6 lg:w-1/6"
-            ),
-            mainContent.SetClass("m-8 w-full mb-24"),
-        ])
-        this.SetClass("h-full block md:flex")
-    }
-}
diff --git a/UI/BigComponents/BackToIndex.ts b/UI/BigComponents/BackToIndex.ts
deleted file mode 100644
index dc35f21395..0000000000
--- a/UI/BigComponents/BackToIndex.ts
+++ /dev/null
@@ -1,16 +0,0 @@
-import { SubtleButton } from "../Base/SubtleButton"
-import Svg from "../../Svg"
-import Translations from "../i18n/Translations"
-import BaseUIElement from "../BaseUIElement"
-
-export default class BackToIndex extends SubtleButton {
-    constructor(message?: string | BaseUIElement) {
-        super(
-            Svg.back_svg().SetStyle("height: 1.5rem;"),
-            message ?? Translations.t.general.backToMapcomplete,
-            {
-                url: "index.html",
-            }
-        )
-    }
-}
diff --git a/UI/NotFound.svelte b/UI/NotFound.svelte
new file mode 100644
index 0000000000..34c6ab212e
--- /dev/null
+++ b/UI/NotFound.svelte
@@ -0,0 +1,14 @@
+<script>
+  import Tr from "./Base/Tr.svelte";
+  import Translations from "./i18n/Translations.ts";
+  import BackButton from "./Base/BackButton.svelte";
+  console.log("???")
+</script>
+<div class="flex flex-col">
+  <Tr t={Translations.t.general["404"]}></Tr>
+  <BackButton clss="m-8" on:click={() => {window.location = "index.html"}}>
+    <div class="flex w-full justify-center">
+    <Tr t={Translations.t.general.backToIndex}></Tr>
+    </div>
+  </BackButton>
+</div>
diff --git a/assets/themes/mapcomplete-changes/mapcomplete-changes.json b/assets/themes/mapcomplete-changes/mapcomplete-changes.json
index f82a920864..336b11205c 100644
--- a/assets/themes/mapcomplete-changes/mapcomplete-changes.json
+++ b/assets/themes/mapcomplete-changes/mapcomplete-changes.json
@@ -1,13 +1,19 @@
 {
   "id": "mapcomplete-changes",
   "title": {
-    "en": "Changes made with MapComplete"
+    "en": "Changes made with MapComplete",
+    "de": "Mit MapComplete erstellte Änderungen",
+    "nl": "Wijzigingen gemaakt met MapComplete"
   },
   "shortDescription": {
-    "en": "Shows changes made by MapComplete"
+    "en": "Show changes made with MapComplete",
+    "de": "Mit MapComplete erstellte Änderungen anzeigen",
+    "nl": "Toon wijzigingen gemaakt met MapComplete"
   },
   "description": {
-    "en": "This maps shows all the changes made with MapComplete"
+    "en": "This maps shows all the changes made with MapComplete",
+    "de": "Diese Karte zeigt alle mit MapComplete vorgenommenen Änderungen",
+    "nl": "Deze kaart toont alle wijzigingen die met MapComplete gemaakt werden"
   },
   "icon": "./assets/svg/logo.svg",
   "hideFromOverview": true,
@@ -20,7 +26,9 @@
     {
       "id": "mapcomplete-changes",
       "name": {
-        "en": "Changeset centers"
+        "en": "Changeset centers",
+        "de": "Zentrum der Änderungssätze",
+        "nl": "Centerpunt van changeset"
       },
       "minzoom": 0,
       "source": {
@@ -31,41 +39,51 @@
       },
       "title": {
         "render": {
-          "en": "Changeset for {theme}"
+          "en": "Changeset for {theme}",
+          "de": "Änderungssatz für {theme}"
         }
       },
       "description": {
-        "en": "Shows all MapComplete changes"
+        "en": "Show all MapComplete changes",
+        "de": "Alle MapComplete-Änderungen anzeigen",
+        "nl": "Toon alle MapComplete wijzigingen"
       },
       "tagRenderings": [
         {
           "id": "show_changeset_id",
           "render": {
-            "en": "Changeset <a href='https://openstreetmap.org/changeset/{id}' target='_blank'>{id}</a>"
+            "en": "Changeset <a href='https://openstreetmap.org/changeset/{id}' target='_blank'>{id}</a>",
+            "de": "Änderungssatz <a href='https://openstreetmap.org/changeset/{id}' target='_blank'>{id}</a>"
           }
         },
         {
           "id": "contributor",
           "question": {
-            "en": "What contributor did make this change?"
+            "en": "Which contributor made this change?",
+            "de": "Welcher Mitwirkende hat diese Änderung vorgenommen?",
+            "nl": "Welke bijdrager maakte deze wijziging?"
           },
           "freeform": {
             "key": "user"
           },
           "render": {
-            "en": "Change made by <a href='https://openstreetmap.org/user/{user}' target='_blank'>{user}</a>"
+            "en": "Change made by <a href='https://openstreetmap.org/user/{user}' target='_blank'>{user}</a>",
+            "de": "Änderung gemacht von <a href='https://openstreetmap.org/user/{user}' target='_blank'>{user}</a>",
+            "nl": "Wijziging gemaakt door  <a href='https://openstreetmap.org/user/{user}' target='_blank'>{user}</a>"
           }
         },
         {
           "id": "theme-id",
           "question": {
-            "en": "What theme was used to make this change?"
+            "en": "What theme was used to make this change?",
+            "de": "Welches Thema wurde für diese Änderung verwendet?\""
           },
           "freeform": {
             "key": "theme"
           },
           "render": {
-            "en": "Change with theme <a href='https://mapcomplete.osm.be/{theme}'>{theme}</a>"
+            "en": "Change with theme <a href='https://mapcomplete.osm.be/{theme}'>{theme}</a>",
+            "de": "Geändert mit Thema <a href='https://mapcomplete.osm.be/{theme}'>{theme}</a>"
           }
         },
         {
@@ -74,19 +92,27 @@
             "key": "locale"
           },
           "question": {
-            "en": "What locale (language) was this change made in?"
+            "en": "What locale (language) was this change made in?",
+            "de": "In welcher Sprache wurde diese Änderung vorgenommen?",
+            "nl": "In welke locale (taal) werd deze wijziging gemaakt?"
           },
           "render": {
-            "en": "User locale is {locale}"
+            "en": "User locale is {locale}",
+            "de": "Usersprache ist {locale}",
+            "nl": "De gebruikerstaal is {locale}"
           }
         },
         {
           "id": "host",
           "render": {
-            "en": "Change with with <a href='{host}'>{host}</a>"
+            "en": "Change made with <a href='{host}'>{host}</a>",
+            "de": "Änderung vorgenommen mit <a href='{host}'>{host}</a>",
+            "nl": "Wijziging gemaakt met <a href='{host}'>{host}</a>"
           },
           "question": {
-            "en": "What host (website) was this change made with?"
+            "en": "What host (website) was this change made with?",
+            "de": "Mit welchem Host / welcher Website wurde diese Änderung gemacht?",
+            "nl": "Met welke host (website) werd deze wijziging gemaakt?"
           },
           "freeform": {
             "key": "host"
@@ -107,10 +133,12 @@
         {
           "id": "version",
           "question": {
-            "en": "What version of MapComplete was used to make this change?"
+            "en": "What version of MapComplete was used to make this change?",
+            "de": "Mit welcher Version von MapComplete wurde diese Änderung gemacht?"
           },
           "render": {
-            "en": "Made with {editor}"
+            "en": "Made with {editor}",
+            "de": "Erstellt mit {editor}"
           },
           "freeform": {
             "key": "editor"
@@ -444,7 +472,9 @@
                 }
               ],
               "question": {
-                "en": "Themename contains {search}"
+                "en": "Theme name contains {search}",
+                "de": "Themenname enthält {search}",
+                "nl": "Themenaam bevat {search}"
               }
             }
           ]
@@ -460,7 +490,9 @@
                 }
               ],
               "question": {
-                "en": "Made by contributor {search}"
+                "en": "Made by contributor {search}",
+                "de": "Erstellt von {search}",
+                "nl": "Gemaakt door bijdrager {search}"
               }
             }
           ]
@@ -476,7 +508,9 @@
                 }
               ],
               "question": {
-                "en": "<b>Not</b> made by contributor {search}"
+                "en": "<b>Not</b> made by contributor {search}",
+                "de": "<b>Nicht</b> erstellt von {search}",
+                "nl": "<b>Niet</b> gemaakt door bijdrager {search}"
               }
             }
           ]
@@ -493,7 +527,9 @@
                 }
               ],
               "question": {
-                "en": "Made before {search}"
+                "en": "Made before {search}",
+                "de": "Erstellt vor {search}",
+                "nl": "Gemaakt voor {search}"
               }
             }
           ]
@@ -510,7 +546,9 @@
                 }
               ],
               "question": {
-                "en": "Made after {search}"
+                "en": "Made after {search}",
+                "de": "Erstellt nach {search}",
+                "nl": "Gemaakt na {search}"
               }
             }
           ]
@@ -526,7 +564,9 @@
                 }
               ],
               "question": {
-                "en": "User language (iso-code) {search}"
+                "en": "User language (iso-code) {search}",
+                "de": "Benutzersprache (ISO-Code) {search}",
+                "nl": "De taal van de bijdrager is {search}"
               }
             }
           ]
@@ -542,7 +582,9 @@
                 }
               ],
               "question": {
-                "en": "Made with host {search}"
+                "en": "Made with host {search}",
+                "de": "Erstellt mit Host {search}",
+                "nl": "Gemaakt met host {search}"
               }
             }
           ]
@@ -553,7 +595,9 @@
             {
               "osmTags": "add-image>0",
               "question": {
-                "en": "Changeset added at least one image"
+                "en": "Changeset added at least one image",
+                "de": "Changeset fügte mindestens ein Bild hinzu",
+                "nl": "Changeset bevat minstens één afbeelding"
               }
             }
           ]
@@ -568,7 +612,8 @@
           {
             "id": "link_to_more",
             "render": {
-              "en": "More statistics can be found <a href='https://github.com/pietervdvn/MapComplete/tree/develop/Docs/Tools/graphs' target='_blank'>here</a>"
+              "en": "More statistics can be found <a href='https://github.com/pietervdvn/MapComplete/tree/develop/Docs/Tools/graphs' target='_blank'>here</a>",
+              "de": "Mehr Statistiken gibt es <a href='https://github.com/pietervdvn/MapComplete/tree/develop/Docs/Tools/graphs' target='_blank'>hier</a>"
             }
           },
           {
diff --git a/langs/ca.json b/langs/ca.json
index 00c82ee33f..d96cbec37b 100644
--- a/langs/ca.json
+++ b/langs/ca.json
@@ -146,7 +146,6 @@
         },
         "back": "Tornar",
         "backToIndex": "Torna a la vista general amb tots els mapes temàtics",
-        "backToMapcomplete": "Tornar a l'explicació general de la petició",
         "backgroundMap": "Mapa de fons",
         "cancel": "Cancel·lar",
         "confirm": "Confirmar",
diff --git a/langs/cs.json b/langs/cs.json
index 12f30043d1..00d662fbd0 100644
--- a/langs/cs.json
+++ b/langs/cs.json
@@ -146,7 +146,6 @@
         },
         "back": "Zpět",
         "backToIndex": "Návrat na přehled všech tematických map",
-        "backToMapcomplete": "Zpět na přehled témat",
         "backgroundMap": "Mapa na pozadí",
         "cancel": "Zrušit",
         "confirm": "Potvrdit",
diff --git a/langs/da.json b/langs/da.json
index b90fe99e1a..9b5e9d7ce0 100644
--- a/langs/da.json
+++ b/langs/da.json
@@ -95,7 +95,6 @@
             "translatedBy": "MapComplete er oversat af {contributors} og <a href=\"https://github.com/pietervdvn/MapComplete/graphs/contributors\" target=\"_blank\">{hiddenCount} flere bidragsydere</a>"
         },
         "back": "Tilbage",
-        "backToMapcomplete": "Tilbage til temaoversigten",
         "backgroundMap": "Baggrundskort",
         "cancel": "Afbryd",
         "confirm": "Bekræft",
diff --git a/langs/de.json b/langs/de.json
index 963bc1af51..47ed513caa 100644
--- a/langs/de.json
+++ b/langs/de.json
@@ -161,7 +161,6 @@
         },
         "back": "Zurück",
         "backToIndex": "Zurück zur Übersicht aller thematischen Karten",
-        "backToMapcomplete": "Zurück zur Themenübersicht",
         "backgroundMap": "Hintergrundkarte auswählen",
         "backgroundSwitch": "Hintergrund wechseln",
         "cancel": "Abbrechen",
diff --git a/langs/en.json b/langs/en.json
index b3107da8c2..61e6a186e2 100644
--- a/langs/en.json
+++ b/langs/en.json
@@ -92,6 +92,7 @@
         "whatIsOsm": "What is OpenStreetMap?"
     },
     "general": {
+        "404": "This page does not exist",
         "about": "Easily edit and add OpenStreetMap for a certain theme",
         "aboutMapComplete": {
             "intro": "Use MapComplete to add OpenStreetMap info on a <b>single theme.</b> Answer questions, and within minutes your contributions are available everywhere. In most themes you can add pictures or even leave a review. The <b>theme maintainer</b> defines elements, questions and languages for it."
@@ -161,7 +162,6 @@
         },
         "back": "Back",
         "backToIndex": "Go back to the overview with all thematic maps",
-        "backToMapcomplete": "Back to the theme overview",
         "backgroundMap": "Select a background layer",
         "backgroundSwitch": "Switch background",
         "cancel": "Cancel",
diff --git a/langs/es.json b/langs/es.json
index 84e55b3c30..4a3d2da7b4 100644
--- a/langs/es.json
+++ b/langs/es.json
@@ -102,7 +102,6 @@
         },
         "back": "Atrás",
         "backToIndex": "Volver a la vista general con todos los mapas temáticos",
-        "backToMapcomplete": "Volver a la vista de temas",
         "backgroundMap": "Mapa de fondo",
         "cancel": "Cancelar",
         "confirm": "Confirmar",
diff --git a/langs/fr.json b/langs/fr.json
index 4a18fdfc60..73846ee81b 100644
--- a/langs/fr.json
+++ b/langs/fr.json
@@ -118,7 +118,6 @@
         },
         "back": "Retour",
         "backToIndex": "Revenir vers l'aperçu de toutes les cartes thématiques",
-        "backToMapcomplete": "Retour à l'aperçu du thème",
         "backgroundMap": "Fond de plan",
         "cancel": "Annuler",
         "confirm": "Confirmer",
diff --git a/langs/hu.json b/langs/hu.json
index 83bea582fe..afd36563bd 100644
--- a/langs/hu.json
+++ b/langs/hu.json
@@ -91,7 +91,6 @@
             "themeBy": "A téma karbantartója: {author}"
         },
         "back": "Vissza",
-        "backToMapcomplete": "Vissza a témák áttekintéséhez",
         "backgroundMap": "Háttértérkép",
         "cancel": "Mégse",
         "confirm": "Megerősítés",
diff --git a/langs/it.json b/langs/it.json
index 68e75e6afe..171f0fcbd3 100644
--- a/langs/it.json
+++ b/langs/it.json
@@ -96,7 +96,6 @@
             "translatedBy": "MapComplete è stata tradotta da {contributors} e da <a href=\"https://github.com/pietervdvn/MapComplete/graphs/contributors\" target=\"_blank\">{hiddenCount} contributori aggiuntivi</a>"
         },
         "back": "Indietro",
-        "backToMapcomplete": "Torna alla panoramica sull'argomento",
         "backgroundMap": "Mappa di sfondo",
         "cancel": "Annulla",
         "confirm": "Conferma",
diff --git a/langs/nb_NO.json b/langs/nb_NO.json
index e9b8bf4e5a..de0ede216a 100644
--- a/langs/nb_NO.json
+++ b/langs/nb_NO.json
@@ -125,7 +125,6 @@
             "translatedBy": "MapComplete har blitt oversatt av {contributors} og <a href=\"https://github.com/pietervdvn/MapComplete/graphs/contributors\" target=\"_blank\">{hiddenCount} andre bidragsytere</a>."
         },
         "back": "Tilbake",
-        "backToMapcomplete": "Tilbake til temaoversikten",
         "backgroundMap": "Bakgrunnskart",
         "cancel": "Avbryt",
         "confirm": "Bekreft",
diff --git a/langs/nl.json b/langs/nl.json
index 6929e2303a..4775dd2602 100644
--- a/langs/nl.json
+++ b/langs/nl.json
@@ -148,7 +148,6 @@
         },
         "back": "Vorige",
         "backToIndex": "Keer terug naar het overzicht met alle thematische kaarten",
-        "backToMapcomplete": "Terug naar het themaoverzicht",
         "backgroundMap": "Selecteer een achtergrondlaag",
         "cancel": "Annuleren",
         "confirm": "Bevestigen",
diff --git a/langs/pt.json b/langs/pt.json
index d73f252986..c6ac285a5b 100644
--- a/langs/pt.json
+++ b/langs/pt.json
@@ -134,7 +134,6 @@
         },
         "back": "Voltar",
         "backToIndex": "Volte para a visão geral com todos os mapas temáticos",
-        "backToMapcomplete": "Voltar à visão geral do tema",
         "backgroundMap": "Mapa de fundo",
         "cancel": "Cancelar",
         "confirm": "Confirmar",
diff --git a/langs/zh_Hant.json b/langs/zh_Hant.json
index 4983f4569a..3d48b102ef 100644
--- a/langs/zh_Hant.json
+++ b/langs/zh_Hant.json
@@ -118,7 +118,6 @@
             "translatedBy": "MapComplete 由 {contributors} 翻譯，而且還有 <a href=\"https://github.com/pietervdvn/MapComplete/graphs/contributors\" target=\"_blank\">{hiddenCount} 更多貢獻者</a>"
         },
         "back": "回去",
-        "backToMapcomplete": "回到主題總覽",
         "backgroundMap": "背景地圖",
         "cancel": "取消",
         "confirm": "確認",
diff --git a/notfound.ts b/notfound.ts
index 0da141d4fd..da596ea9d4 100644
--- a/notfound.ts
+++ b/notfound.ts
@@ -1,5 +1,4 @@
-import { FixedUiElement } from "./UI/Base/FixedUiElement"
-import Combine from "./UI/Base/Combine"
-import BackToIndex from "./UI/BigComponents/BackToIndex"
+import SvelteUIElement from "./UI/Base/SvelteUIElement"
+import NotFound from "./UI/NotFound.svelte"
 
-new Combine([new FixedUiElement("This page is not found"), new BackToIndex()]).AttachTo("maindiv")
+new SvelteUIElement(NotFound, {}).AttachTo("maindiv")