diff --git a/src/app/components/CalendarEventForm.svelte b/src/app/components/CalendarEventForm.svelte
index 42e44ac5..cdbf78c4 100644
--- a/src/app/components/CalendarEventForm.svelte
+++ b/src/app/components/CalendarEventForm.svelte
@@ -36,7 +36,9 @@
 
   const back = () => history.back()
 
-  const submit = () => {
+  const selectFiles = () => editor.then(ed => ed.chain().selectFiles().run())
+
+  const submit = async () => {
     if ($uploading) return
 
     if (!title) {
@@ -60,8 +62,9 @@
       })
     }
 
+    const ed = await editor
     const event = createEvent(EVENT_TIME, {
-      content: editor.getText({blockSeparator: "\n"}).trim(),
+      content: ed.getText({blockSeparator: "\n"}).trim(),
       tags: [
         ["d", initialValues?.d || randomId()],
         ["title", title],
@@ -69,7 +72,7 @@
         ["start", start.toString()],
         ["end", end.toString()],
         ...daysBetween(start, end).map(D => ["D", D.toString()]),
-        ...editor.storage.nostr.getEditorTags(),
+        ...ed.storage.nostr.getEditorTags(),
         tagRoom(GENERAL, url),
         PROTECTED,
       ],
@@ -119,10 +122,7 @@
         <div class="input-editor flex-grow overflow-hidden">
           <EditorContent {editor} />
         </div>
-        <Button
-          data-tip="Add an image"
-          class="center btn tooltip"
-          onclick={() => editor.chain().selectFiles().run()}>
+        <Button data-tip="Add an image" class="center btn tooltip" onclick={selectFiles}>
           {#if $uploading}
             <span class="loading loading-spinner loading-xs"></span>
           {:else}
diff --git a/src/app/components/ChannelCompose.svelte b/src/app/components/ChannelCompose.svelte
index 82e49f67..e1a683aa 100644
--- a/src/app/components/ChannelCompose.svelte
+++ b/src/app/components/ChannelCompose.svelte
@@ -18,21 +18,22 @@
 
   const uploading = writable(false)
 
-  export const focus = () => editor.chain().focus().run()
+  export const focus = () => editor.then(ed => ed.chain().focus().run())
 
-  const uploadFiles = () => editor.chain().selectFiles().run()
+  const uploadFiles = () => editor.then(ed => ed.chain().selectFiles().run())
 
-  const submit = () => {
+  const submit = async () => {
     if ($uploading) return
 
-    const content = editor.getText({blockSeparator: "\n"}).trim()
-    const tags = editor.storage.nostr.getEditorTags()
+    const ed = await editor
+    const content = ed.getText({blockSeparator: "\n"}).trim()
+    const tags = ed.storage.nostr.getEditorTags()
 
     if (!content) return
 
     onSubmit({content, tags})
 
-    editor.chain().clearContent().run()
+    ed.chain().clearContent().run()
   }
 
   const editor = makeEditor({url, autofocus, submit, uploading, aggressive: true})
diff --git a/src/app/components/EventReply.svelte b/src/app/components/EventReply.svelte
index 2b54c051..13207216 100644
--- a/src/app/components/EventReply.svelte
+++ b/src/app/components/EventReply.svelte
@@ -16,11 +16,14 @@
 
   const uploading = writable(false)
 
-  const submit = () => {
+  const selectFiles = () => editor.then(ed => ed.commands.selectFiles())
+
+  const submit = async () => {
     if ($uploading) return
 
-    const content = editor.getText({blockSeparator: "\n"}).trim()
-    const tags = [...editor.storage.nostr.getEditorTags(), tagRoom(GENERAL, url), PROTECTED]
+    const ed = await editor
+    const content = ed.getText({blockSeparator: "\n"}).trim()
+    const tags = [...ed.storage.nostr.getEditorTags(), tagRoom(GENERAL, url), PROTECTED]
 
     if (!content) {
       return pushToast({
@@ -68,7 +71,7 @@
       <Button
         data-tip="Add an image"
         class="tooltip tooltip-left absolute bottom-1 right-2"
-        onclick={editor.commands.selectFiles}>
+        onclick={selectFiles}>
         {#if $uploading}
           <span class="loading loading-spinner loading-xs"></span>
         {:else}
diff --git a/src/app/components/ThreadCreate.svelte b/src/app/components/ThreadCreate.svelte
index 17ce3986..d0a16c64 100644
--- a/src/app/components/ThreadCreate.svelte
+++ b/src/app/components/ThreadCreate.svelte
@@ -19,7 +19,9 @@
 
   const back = () => history.back()
 
-  const submit = () => {
+  const selectFiles = () => editor.then(ed => ed.commands.selectFiles())
+
+  const submit = async () => {
     if ($uploading) return
 
     if (!title) {
@@ -29,7 +31,8 @@
       })
     }
 
-    const content = editor.getText({blockSeparator: "\n"}).trim()
+    const ed = await editor
+    const content = ed.getText({blockSeparator: "\n"}).trim()
 
     if (!content.trim()) {
       return pushToast({
@@ -39,7 +42,7 @@
     }
 
     const tags = [
-      ...editor.storage.nostr.getEditorTags(),
+      ...ed.storage.nostr.getEditorTags(),
       tagRoom(GENERAL, url),
       ["title", title],
       PROTECTED,
@@ -97,7 +100,7 @@
     <Button
       data-tip="Add an image"
       class="tooltip tooltip-left absolute bottom-1 right-2"
-      onclick={editor.commands.selectFiles}>
+      onclick={selectFiles}>
       {#if $uploading}
         <span class="loading loading-spinner loading-xs"></span>
       {:else}
diff --git a/src/app/editor/EditorContent.svelte b/src/app/editor/EditorContent.svelte
index c6b40d6c..6b56f9c6 100644
--- a/src/app/editor/EditorContent.svelte
+++ b/src/app/editor/EditorContent.svelte
@@ -1,22 +1,29 @@
 <script lang="ts">
+  import {Editor} from "@welshman/editor"
   import {onDestroy, onMount} from "svelte"
 
-  const {editor} = $props()
+  type Props = {
+    editor: Promise<Editor>
+  }
+
+  const {editor}: Props = $props()
 
   let element: HTMLElement
 
   onMount(() => {
-    if (editor.options.element) {
-      element?.append(editor.options.element)
-    }
+    editor.then(({options}) => {
+      if (options.element) {
+        element?.append(options.element)
+      }
 
-    if (editor.options.autofocus) {
-      ;(element?.querySelector("[contenteditable]") as HTMLElement)?.focus()
-    }
+      if (options.autofocus) {
+        ;(element?.querySelector("[contenteditable]") as HTMLElement)?.focus()
+      }
+    })
   })
 
   onDestroy(() => {
-    editor.destroy()
+    editor.then($editor => $editor.destroy())
   })
 </script>
 
diff --git a/src/app/editor/index.ts b/src/app/editor/index.ts
index b1750df9..c11f8927 100644
--- a/src/app/editor/index.ts
+++ b/src/app/editor/index.ts
@@ -2,15 +2,58 @@ import {mount} from "svelte"
 import type {Writable} from "svelte/store"
 import {get} from "svelte/store"
 import type {StampedEvent} from "@welshman/util"
-import {getTagValue, getListTags} from "@welshman/util"
+import {makeEvent, getTagValues, getListTags, BLOSSOM_AUTH} from "@welshman/util"
+import {simpleCache, removeNil, now} from "@welshman/lib"
 import {Router} from "@welshman/router"
 import {signer, profileSearch, userBlossomServers} from "@welshman/app"
 import {Editor, MentionSuggestion, WelshmanExtension} from "@welshman/editor"
 import {makeMentionNodeView} from "./MentionNodeView"
 import ProfileSuggestion from "./ProfileSuggestion.svelte"
 
-export const getUploadUrl = () =>
-  getTagValue("server", getListTags(userBlossomServers.get())) || "https://cdn.satellite.earth"
+export const hasBlossomSupport = simpleCache(async ([url]: [string]) => {
+  try {
+    const event = await signer.get()!.sign(
+      makeEvent(BLOSSOM_AUTH, {
+        tags: [
+          ["t", "upload"],
+          ["server", url],
+          ["expiration", String(now() + 30)],
+        ],
+      }),
+    )
+
+    const res = await fetch(url + "/upload", {
+      method: "head",
+      headers: {
+        Authorization: `Nostr ${btoa(JSON.stringify(event))}`,
+        "X-Content-Type": "text/plain",
+        "X-Content-Length": "1",
+        "X-SHA-256": "73cb3858a687a8494ca3323053016282f3dad39d42cf62ca4e79dda2aac7d9ac",
+      },
+    })
+
+    return res.status === 200
+  } catch (e) {
+    if (!String(e).includes("Failed to fetch")) {
+      console.error(e)
+    }
+  }
+})
+
+export const getUploadUrl = async (spaceUrl?: string) => {
+  const userUrls = getTagValues("server", getListTags(userBlossomServers.get()))
+  const allUrls = removeNil([spaceUrl, ...userUrls])
+
+  for (let url of allUrls) {
+    url = url.replace(/wss?:\/\//, "https://")
+
+    if (await hasBlossomSupport(url)) {
+      return url
+    }
+  }
+
+  return "https://cdn.satellite.earth"
+}
 
 export const signWithAssert = async (template: StampedEvent) => {
   const event = await signer.get().sign(template)
@@ -18,7 +61,7 @@ export const signWithAssert = async (template: StampedEvent) => {
   return event!
 }
 
-export const makeEditor = ({
+export const makeEditor = async ({
   aggressive = false,
   autofocus = false,
   charCount,
@@ -26,7 +69,6 @@ export const makeEditor = ({
   placeholder = "",
   url,
   submit,
-  uploadUrl = getUploadUrl(),
   uploading,
   wordCount,
 }: {
@@ -37,11 +79,10 @@ export const makeEditor = ({
   placeholder?: string
   url?: string
   submit: () => void
-  uploadUrl?: string
   uploading?: Writable<boolean>
   wordCount?: Writable<number>
-}) =>
-  new Editor({
+}) => {
+  return new Editor({
     content,
     autofocus,
     element: document.createElement("div"),
@@ -50,7 +91,7 @@ export const makeEditor = ({
         submit,
         sign: signWithAssert,
         defaultUploadType: "blossom",
-        defaultUploadUrl: uploadUrl,
+        defaultUploadUrl: await getUploadUrl(url),
         extensions: {
           placeholder: {
             config: {
@@ -101,3 +142,4 @@ export const makeEditor = ({
       charCount?.set(editor.storage.wordCount.chars)
     },
   })
+}
diff --git a/src/routes/spaces/[relay]/+layout.svelte b/src/routes/spaces/[relay]/+layout.svelte
index ccacf48b..b344a914 100644
--- a/src/routes/spaces/[relay]/+layout.svelte
+++ b/src/routes/spaces/[relay]/+layout.svelte
@@ -10,6 +10,7 @@
   import SpaceAuthError from "@app/components/SpaceAuthError.svelte"
   import {pushToast} from "@app/toast"
   import {pushModal} from "@app/modal"
+  import {getUploadUrl} from "@app/editor"
   import {setChecked} from "@app/notifications"
   import {checkRelayConnection, checkRelayAuth, checkRelayAccess} from "@app/commands"
   import {decodeRelay, userRoomsByUrl} from "@app/state"
@@ -51,6 +52,9 @@
   onMount(() => {
     checkConnection()
 
+    // Prime our cache so inputs show up quickly
+    getUploadUrl(url)
+
     const relays = [url]
     const since = ago(WEEK)
     const controller = new AbortController()