diff --git a/packages/bbui/src/Form/Core/Dropzone.svelte b/packages/bbui/src/Form/Core/Dropzone.svelte
index bbaf5a3ff9..f7fed78b70 100644
--- a/packages/bbui/src/Form/Core/Dropzone.svelte
+++ b/packages/bbui/src/Form/Core/Dropzone.svelte
@@ -22,6 +22,7 @@
   export let error = null
   export let fileTags = []
   export let maximum = null
+  export let extensions = "*"
 
   const dispatch = createEventDispatcher()
   const imageExtensions = [
@@ -207,6 +208,7 @@
           {disabled}
           type="file"
           multiple
+          accept={extensions}
           on:change={handleFile}
         />
         <svg
diff --git a/packages/builder/cypress/integration/addMultiOptionDatatype.spec.js b/packages/builder/cypress/integration/addMultiOptionDatatype.spec.js
index d708c7bc0b..1b67c1b3fc 100644
--- a/packages/builder/cypress/integration/addMultiOptionDatatype.spec.js
+++ b/packages/builder/cypress/integration/addMultiOptionDatatype.spec.js
@@ -39,4 +39,4 @@ context("Add Multi-Option Datatype", () => {
         })
     })
   })
-})
+
diff --git a/packages/builder/cypress/support/commands.js b/packages/builder/cypress/support/commands.js
index 5952f4699c..e69bc8badc 100644
--- a/packages/builder/cypress/support/commands.js
+++ b/packages/builder/cypress/support/commands.js
@@ -43,6 +43,7 @@ Cypress.Commands.add("createApp", name => {
       }
     })
   cy.contains(/Start from scratch/).dblclick()
+  cy.wait(2000)
   cy.get(".spectrum-Modal").within(() => {
     cy.get("input").eq(0).type(name).should("have.value", name).blur()
     cy.get(".spectrum-ButtonGroup").contains("Create app").click()
diff --git a/packages/client/manifest.json b/packages/client/manifest.json
index 9431129fa0..e618ca1c11 100644
--- a/packages/client/manifest.json
+++ b/packages/client/manifest.json
@@ -2236,7 +2236,7 @@
           "setting": "optionsSource",
           "value": "provider"
         }
-      }, 
+      },
       {
         "type": "options",
         "key": "customOptions",
@@ -2419,6 +2419,11 @@
         "label": "Label",
         "key": "label"
       },
+      {
+        "type": "text",
+        "label": "Extensions",
+        "key": "extensions"
+      },
       {
         "type": "boolean",
         "label": "Disabled",
diff --git a/packages/client/src/components/app/forms/AttachmentField.svelte b/packages/client/src/components/app/forms/AttachmentField.svelte
index 8c4eaea243..4d8a0b482d 100644
--- a/packages/client/src/components/app/forms/AttachmentField.svelte
+++ b/packages/client/src/components/app/forms/AttachmentField.svelte
@@ -7,6 +7,7 @@
   export let label
   export let disabled = false
   export let validation
+  export let extensions
 
   let fieldState
   let fieldApi
@@ -52,6 +53,7 @@
       }}
       {processFiles}
       {handleFileTooLarge}
+      {extensions}
     />
   {/if}
 </Field>
diff --git a/packages/client/src/components/app/forms/InnerForm.svelte b/packages/client/src/components/app/forms/InnerForm.svelte
index 47bc717d92..c1e92bf442 100644
--- a/packages/client/src/components/app/forms/InnerForm.svelte
+++ b/packages/client/src/components/app/forms/InnerForm.svelte
@@ -141,8 +141,18 @@
         return
       }
 
+      // Create validation function based on field schema
+      const schemaConstraints = schema?.[field]?.constraints
+      const validator = createValidatorFromConstraints(
+        schemaConstraints,
+        validationRules,
+        field,
+        table
+      )
+
       // If we've already registered this field then keep some existing state
       let initialValue = deepGet(initialValues, field) ?? defaultValue
+      let initialError = null
       let fieldId = `id-${generateID()}`
       const existingField = getField(field)
       if (existingField) {
@@ -156,20 +166,17 @@
         } else {
           initialValue = fieldState.value ?? initialValue
         }
+
+        // If this field has already been registered and we previously had an
+        // error set, then re-run the validator to see if we can unset it
+        if (fieldState.error) {
+          initialError = validator(initialValue)
+        }
       }
 
       // Auto columns are always disabled
       const isAutoColumn = !!schema?.[field]?.autocolumn
 
-      // Create validation function based on field schema
-      const schemaConstraints = schema?.[field]?.constraints
-      const validator = createValidatorFromConstraints(
-        schemaConstraints,
-        validationRules,
-        field,
-        table
-      )
-
       // Construct field info
       const fieldInfo = writable({
         name: field,
@@ -178,7 +185,7 @@
         fieldState: {
           fieldId,
           value: initialValue,
-          error: null,
+          error: initialError,
           disabled: disabled || fieldDisabled || isAutoColumn,
           defaultValue,
           validator,
diff --git a/packages/client/src/components/app/forms/MultiFieldSelect.svelte b/packages/client/src/components/app/forms/MultiFieldSelect.svelte
index cecc569b6f..686198dfe1 100644
--- a/packages/client/src/components/app/forms/MultiFieldSelect.svelte
+++ b/packages/client/src/components/app/forms/MultiFieldSelect.svelte
@@ -20,6 +20,7 @@
   let fieldSchema
 
   $: flatOptions = optionsSource == null || optionsSource === "schema"
+  $: expandedDefaultValue = expand(defaultValue)
   $: options = getOptions(
     optionsSource,
     fieldSchema,
@@ -28,6 +29,18 @@
     valueColumn,
     customOptions
   )
+
+  const expand = values => {
+    if (!values) {
+      return []
+    }
+
+    if (Array.isArray(values)) {
+      return values
+    }
+
+    return values.split(",").map(value => value.trim())
+  }
 </script>
 
 <Field
@@ -35,7 +48,7 @@
   {label}
   {disabled}
   {validation}
-  {defaultValue}
+  defaultValue={expandedDefaultValue}
   type="array"
   bind:fieldState
   bind:fieldApi