diff --git a/inst/apps/122-async-outputs/tests/testthat/test-mytest.R b/inst/apps/122-async-outputs/tests/testthat/test-mytest.R
index 8ca7834e22..a8d7576ca2 100644
--- a/inst/apps/122-async-outputs/tests/testthat/test-mytest.R
+++ b/inst/apps/122-async-outputs/tests/testthat/test-mytest.R
@@ -1,7 +1,14 @@
 library(shinytest2)
 
 test_that("Migrated shinytest test: mytest.R", {
-  app <- AppDriver$new(load_timeout = 15000, seed = 100, shiny_args = list(display.mode = "normal"))
+  app <- AppDriver$new(
+    load_timeout = 15000, seed = 100, 
+    shiny_args = list(display.mode = "normal"),
+    # Use legacy datatable implementation just for the 
+    # info$datatable$colnames test below. We could, of course, 
+    # update that test, but it's also good to test the legacy.
+    options = list(shiny.legacy.datatable = TRUE)
+  )
 
   # Wait until an async value is available
   app$wait_for_value(output = "printa", timeout = 10 * 1000)
diff --git a/inst/apps/126-async-ticks/tests/testthat/_snaps/linux-4.0/mytest/001.json b/inst/apps/126-async-ticks/tests/testthat/_snaps/linux-4.0/mytest/001.json
index 0056f7b36a..09f1fbdb0e 100644
--- a/inst/apps/126-async-ticks/tests/testthat/_snaps/linux-4.0/mytest/001.json
+++ b/inst/apps/126-async-ticks/tests/testthat/_snaps/linux-4.0/mytest/001.json
@@ -3,22 +3,16 @@
 
   },
   "output": {
-    "datatable": {
-      "message": "OK",
-      "call": "NULL",
-      "type": [
-        "shiny.silent.error",
-        "validation"
-      ]
-    },
-    "datatablea": {
-      "message": "OK",
-      "call": "NULL",
-      "type": [
-        "shiny.silent.error",
-        "validation"
-      ]
-    },
+    "datatable": [
+      "OK",
+      "NULL",
+      "c(\"shiny.silent.error\", \"validation\")"
+    ],
+    "datatablea": [
+      "OK",
+      "NULL",
+      "c(\"shiny.silent.error\", \"validation\")"
+    ],
     "image": {
       "message": "OK",
       "call": "NULL",
diff --git a/inst/apps/126-async-ticks/tests/testthat/_snaps/linux-4.1/mytest/001.json b/inst/apps/126-async-ticks/tests/testthat/_snaps/linux-4.1/mytest/001.json
index 0056f7b36a..09f1fbdb0e 100644
--- a/inst/apps/126-async-ticks/tests/testthat/_snaps/linux-4.1/mytest/001.json
+++ b/inst/apps/126-async-ticks/tests/testthat/_snaps/linux-4.1/mytest/001.json
@@ -3,22 +3,16 @@
 
   },
   "output": {
-    "datatable": {
-      "message": "OK",
-      "call": "NULL",
-      "type": [
-        "shiny.silent.error",
-        "validation"
-      ]
-    },
-    "datatablea": {
-      "message": "OK",
-      "call": "NULL",
-      "type": [
-        "shiny.silent.error",
-        "validation"
-      ]
-    },
+    "datatable": [
+      "OK",
+      "NULL",
+      "c(\"shiny.silent.error\", \"validation\")"
+    ],
+    "datatablea": [
+      "OK",
+      "NULL",
+      "c(\"shiny.silent.error\", \"validation\")"
+    ],
     "image": {
       "message": "OK",
       "call": "NULL",
diff --git a/inst/apps/126-async-ticks/tests/testthat/_snaps/linux-4.2/mytest/001.json b/inst/apps/126-async-ticks/tests/testthat/_snaps/linux-4.2/mytest/001.json
index 0056f7b36a..09f1fbdb0e 100644
--- a/inst/apps/126-async-ticks/tests/testthat/_snaps/linux-4.2/mytest/001.json
+++ b/inst/apps/126-async-ticks/tests/testthat/_snaps/linux-4.2/mytest/001.json
@@ -3,22 +3,16 @@
 
   },
   "output": {
-    "datatable": {
-      "message": "OK",
-      "call": "NULL",
-      "type": [
-        "shiny.silent.error",
-        "validation"
-      ]
-    },
-    "datatablea": {
-      "message": "OK",
-      "call": "NULL",
-      "type": [
-        "shiny.silent.error",
-        "validation"
-      ]
-    },
+    "datatable": [
+      "OK",
+      "NULL",
+      "c(\"shiny.silent.error\", \"validation\")"
+    ],
+    "datatablea": [
+      "OK",
+      "NULL",
+      "c(\"shiny.silent.error\", \"validation\")"
+    ],
     "image": {
       "message": "OK",
       "call": "NULL",
diff --git a/inst/apps/126-async-ticks/tests/testthat/_snaps/linux-4.3/mytest/001.json b/inst/apps/126-async-ticks/tests/testthat/_snaps/linux-4.3/mytest/001.json
index 0056f7b36a..09f1fbdb0e 100644
--- a/inst/apps/126-async-ticks/tests/testthat/_snaps/linux-4.3/mytest/001.json
+++ b/inst/apps/126-async-ticks/tests/testthat/_snaps/linux-4.3/mytest/001.json
@@ -3,22 +3,16 @@
 
   },
   "output": {
-    "datatable": {
-      "message": "OK",
-      "call": "NULL",
-      "type": [
-        "shiny.silent.error",
-        "validation"
-      ]
-    },
-    "datatablea": {
-      "message": "OK",
-      "call": "NULL",
-      "type": [
-        "shiny.silent.error",
-        "validation"
-      ]
-    },
+    "datatable": [
+      "OK",
+      "NULL",
+      "c(\"shiny.silent.error\", \"validation\")"
+    ],
+    "datatablea": [
+      "OK",
+      "NULL",
+      "c(\"shiny.silent.error\", \"validation\")"
+    ],
     "image": {
       "message": "OK",
       "call": "NULL",
diff --git a/inst/apps/126-async-ticks/tests/testthat/_snaps/mac-4.0/mytest/001.json b/inst/apps/126-async-ticks/tests/testthat/_snaps/mac-4.0/mytest/001.json
index 0056f7b36a..09f1fbdb0e 100644
--- a/inst/apps/126-async-ticks/tests/testthat/_snaps/mac-4.0/mytest/001.json
+++ b/inst/apps/126-async-ticks/tests/testthat/_snaps/mac-4.0/mytest/001.json
@@ -3,22 +3,16 @@
 
   },
   "output": {
-    "datatable": {
-      "message": "OK",
-      "call": "NULL",
-      "type": [
-        "shiny.silent.error",
-        "validation"
-      ]
-    },
-    "datatablea": {
-      "message": "OK",
-      "call": "NULL",
-      "type": [
-        "shiny.silent.error",
-        "validation"
-      ]
-    },
+    "datatable": [
+      "OK",
+      "NULL",
+      "c(\"shiny.silent.error\", \"validation\")"
+    ],
+    "datatablea": [
+      "OK",
+      "NULL",
+      "c(\"shiny.silent.error\", \"validation\")"
+    ],
     "image": {
       "message": "OK",
       "call": "NULL",
diff --git a/inst/apps/126-async-ticks/tests/testthat/_snaps/mac-4.1/mytest/001.json b/inst/apps/126-async-ticks/tests/testthat/_snaps/mac-4.1/mytest/001.json
index 0056f7b36a..09f1fbdb0e 100644
--- a/inst/apps/126-async-ticks/tests/testthat/_snaps/mac-4.1/mytest/001.json
+++ b/inst/apps/126-async-ticks/tests/testthat/_snaps/mac-4.1/mytest/001.json
@@ -3,22 +3,16 @@
 
   },
   "output": {
-    "datatable": {
-      "message": "OK",
-      "call": "NULL",
-      "type": [
-        "shiny.silent.error",
-        "validation"
-      ]
-    },
-    "datatablea": {
-      "message": "OK",
-      "call": "NULL",
-      "type": [
-        "shiny.silent.error",
-        "validation"
-      ]
-    },
+    "datatable": [
+      "OK",
+      "NULL",
+      "c(\"shiny.silent.error\", \"validation\")"
+    ],
+    "datatablea": [
+      "OK",
+      "NULL",
+      "c(\"shiny.silent.error\", \"validation\")"
+    ],
     "image": {
       "message": "OK",
       "call": "NULL",
diff --git a/inst/apps/126-async-ticks/tests/testthat/_snaps/mac-4.2/mytest/001.json b/inst/apps/126-async-ticks/tests/testthat/_snaps/mac-4.2/mytest/001.json
index 0056f7b36a..09f1fbdb0e 100644
--- a/inst/apps/126-async-ticks/tests/testthat/_snaps/mac-4.2/mytest/001.json
+++ b/inst/apps/126-async-ticks/tests/testthat/_snaps/mac-4.2/mytest/001.json
@@ -3,22 +3,16 @@
 
   },
   "output": {
-    "datatable": {
-      "message": "OK",
-      "call": "NULL",
-      "type": [
-        "shiny.silent.error",
-        "validation"
-      ]
-    },
-    "datatablea": {
-      "message": "OK",
-      "call": "NULL",
-      "type": [
-        "shiny.silent.error",
-        "validation"
-      ]
-    },
+    "datatable": [
+      "OK",
+      "NULL",
+      "c(\"shiny.silent.error\", \"validation\")"
+    ],
+    "datatablea": [
+      "OK",
+      "NULL",
+      "c(\"shiny.silent.error\", \"validation\")"
+    ],
     "image": {
       "message": "OK",
       "call": "NULL",
diff --git a/inst/apps/126-async-ticks/tests/testthat/_snaps/mac-4.3/mytest/001.json b/inst/apps/126-async-ticks/tests/testthat/_snaps/mac-4.3/mytest/001.json
index 0056f7b36a..09f1fbdb0e 100644
--- a/inst/apps/126-async-ticks/tests/testthat/_snaps/mac-4.3/mytest/001.json
+++ b/inst/apps/126-async-ticks/tests/testthat/_snaps/mac-4.3/mytest/001.json
@@ -3,22 +3,16 @@
 
   },
   "output": {
-    "datatable": {
-      "message": "OK",
-      "call": "NULL",
-      "type": [
-        "shiny.silent.error",
-        "validation"
-      ]
-    },
-    "datatablea": {
-      "message": "OK",
-      "call": "NULL",
-      "type": [
-        "shiny.silent.error",
-        "validation"
-      ]
-    },
+    "datatable": [
+      "OK",
+      "NULL",
+      "c(\"shiny.silent.error\", \"validation\")"
+    ],
+    "datatablea": [
+      "OK",
+      "NULL",
+      "c(\"shiny.silent.error\", \"validation\")"
+    ],
     "image": {
       "message": "OK",
       "call": "NULL",
diff --git a/inst/apps/126-async-ticks/tests/testthat/_snaps/windows-4.1/mytest/001.json b/inst/apps/126-async-ticks/tests/testthat/_snaps/windows-4.1/mytest/001.json
index 0056f7b36a..09f1fbdb0e 100644
--- a/inst/apps/126-async-ticks/tests/testthat/_snaps/windows-4.1/mytest/001.json
+++ b/inst/apps/126-async-ticks/tests/testthat/_snaps/windows-4.1/mytest/001.json
@@ -3,22 +3,16 @@
 
   },
   "output": {
-    "datatable": {
-      "message": "OK",
-      "call": "NULL",
-      "type": [
-        "shiny.silent.error",
-        "validation"
-      ]
-    },
-    "datatablea": {
-      "message": "OK",
-      "call": "NULL",
-      "type": [
-        "shiny.silent.error",
-        "validation"
-      ]
-    },
+    "datatable": [
+      "OK",
+      "NULL",
+      "c(\"shiny.silent.error\", \"validation\")"
+    ],
+    "datatablea": [
+      "OK",
+      "NULL",
+      "c(\"shiny.silent.error\", \"validation\")"
+    ],
     "image": {
       "message": "OK",
       "call": "NULL",
diff --git a/inst/apps/126-async-ticks/tests/testthat/_snaps/windows-4.3/mytest/001.json b/inst/apps/126-async-ticks/tests/testthat/_snaps/windows-4.3/mytest/001.json
index 0056f7b36a..09f1fbdb0e 100644
--- a/inst/apps/126-async-ticks/tests/testthat/_snaps/windows-4.3/mytest/001.json
+++ b/inst/apps/126-async-ticks/tests/testthat/_snaps/windows-4.3/mytest/001.json
@@ -3,22 +3,16 @@
 
   },
   "output": {
-    "datatable": {
-      "message": "OK",
-      "call": "NULL",
-      "type": [
-        "shiny.silent.error",
-        "validation"
-      ]
-    },
-    "datatablea": {
-      "message": "OK",
-      "call": "NULL",
-      "type": [
-        "shiny.silent.error",
-        "validation"
-      ]
-    },
+    "datatable": [
+      "OK",
+      "NULL",
+      "c(\"shiny.silent.error\", \"validation\")"
+    ],
+    "datatablea": [
+      "OK",
+      "NULL",
+      "c(\"shiny.silent.error\", \"validation\")"
+    ],
     "image": {
       "message": "OK",
       "call": "NULL",