Adjust ember-try config and compatibility

README.md

@@ -18,7 +18,7 @@
 
 ----
 
-* Ember.js v3.20 or above
+* Ember.js v3.20 through v5.12
 * Ember CLI v3.13 or above
 * Node.js v12 or above
 
@@ -37,7 +37,7 @@ Just drop an `<AttachTooltip/>` or `<AttachPopover/>` in a parent and your float
 <button class="other-button">
   No click me!
 
-  <AttachPopover 
+  <AttachPopover
       @class='ember-attacher'
       @hideOn='click'
       @isShown={{true}}
@@ -93,11 +93,11 @@ Below is a list of all available options, along with their defaults.
 
   // Whether or not an arrow will be displayed next to the attachment.
   arrow: false,
-    
+
   // Add listeners that will automatically call an update function
   // Pass `true` to use the Floating UI default options or Options object to override them
   // Example: { ancestorScroll: false }
-  // For more details see https://floating-ui.com/docs/autoUpdate 
+  // For more details see https://floating-ui.com/docs/autoUpdate
   autoUpdate: false,
 
   // A class that will be applied to the attachment.
@@ -178,8 +178,8 @@ Below is a list of all available options, along with their defaults.
   // showing and hiding of popovers and tooltips.
   useCapture: false,
 
-  // The default padding if collision happens. Set "false" if no collision prevention needed 
-  overflowPadding: 5 
+  // The default padding if collision happens. Set "false" if no collision prevention needed
+  overflowPadding: 5
 }
 ```
 
@@ -265,7 +265,7 @@ test('example', async function(assert) {
     <button id="toggle">
       Click me, captain!
 
-      <AttachPopover 
+      <AttachPopover
           @id='attachment'
           @hideOn='click'
           @showOn='click'

tests/dummy/config/ember-try.js

@@ -32,8 +32,17 @@ module.exports = async function () {
           },
         },
       },
+      {
+        name: 'ember-lts-5.12',
+        npm: {
+          devDependencies: {
+            'ember-source': '~5.12.0',
+          },
+        },
+      },
       {
         name: 'ember-release',
+        allowedToFail: true,
         npm: {
           devDependencies: {
             'ember-source': await getChannelURL('release'),