diff --git a/src/browserforce.ts b/src/browserforce.ts
index 7cc59b72..117ec494 100644
--- a/src/browserforce.ts
+++ b/src/browserforce.ts
@@ -173,11 +173,9 @@ export default class Browserforce {
     const instanceUrl = this.getInstanceUrl();
     // acme.my.salesforce.com
     // acme--<sandboxName>.csN.my.salesforce.com
-    const matches = instanceUrl.match(
-      /https\:\/\/([^.]*)\.my\.salesforce\.com/
-    );
+    const matches = instanceUrl.match(/https\:\/\/(.*)\.my\.salesforce\.com/);
     if (matches) {
-      return matches[1];
+      return matches[1].split('.')[0];
     }
     return null;
   }
@@ -185,10 +183,15 @@ export default class Browserforce {
   public getInstanceDomain() {
     const instanceUrl = this.getInstanceUrl();
     // csN.salesforce.com
-    const matches = instanceUrl.match(/https\:\/\/([^.]*)\.salesforce\.com/);
+    // acme--<sandboxName>.csN.my.salesforce.com
+    // NOT: test.salesforce.com login.salesforce.com
+    const matches = instanceUrl.match(/https\:\/\/(.*)\.salesforce\.com/);
     if (matches) {
-      if (!['test', 'login'].includes(matches[1])) {
-        return matches[1];
+      const parts = matches[1].split('.');
+      if (parts.length === 3 && parts[2] === 'my') {
+        return parts[1];
+      } else if (!['test', 'login'].includes(parts[0])) {
+        return parts[0];
       }
     }
     return null;
diff --git a/src/plugins/communities/index.ts b/src/plugins/communities/index.ts
index ce0e0023..9e5b7913 100644
--- a/src/plugins/communities/index.ts
+++ b/src/plugins/communities/index.ts
@@ -50,14 +50,15 @@ export default class Communities extends BrowserforcePlugin {
       config.domainName ||
       this.browserforce.getMyDomain() ||
       `comm-${Math.random()
-        .toString()
-        .substr(-22)}`
+        .toString(36)
+        .substr(2)}`
     ).substring(0, 22);
     await frameOrPage.waitFor(SELECTORS.DOMAIN_NAME_INPUT_TEXT);
     await frameOrPage.type(SELECTORS.DOMAIN_NAME_INPUT_TEXT, domainName);
     page.on('dialog', async dialog => {
       await dialog.accept();
     });
+    await frameOrPage.waitFor(SELECTORS.SAVE_BUTTON);
     await Promise.all([
       page.waitForNavigation(),
       frameOrPage.click(SELECTORS.SAVE_BUTTON)
diff --git a/test/browserforce.e2e-spec.ts b/test/browserforce.e2e-spec.ts
index 2002b654..41abd621 100644
--- a/test/browserforce.e2e-spec.ts
+++ b/test/browserforce.e2e-spec.ts
@@ -28,4 +28,43 @@ describe('Browser', () => {
       bf.logout();
     });
   });
+  describe('getMyDomain()', () => {
+    it('should determine a my domain for a scratch org', async function() {
+      this.timeout(1000 * 300);
+      this.slow(1000 * 30);
+      const defaultScratchOrg = await core.Org.create({});
+      const ux = await UX.create();
+      const bf = new Browserforce(defaultScratchOrg, ux.cli);
+      await bf.login();
+      const myDomain = bf.getMyDomain();
+      assert.notDeepEqual(null, myDomain);
+      await bf.logout();
+    });
+  });
+  describe('getInstanceDomain()', () => {
+    it('should determine an instance domain for a scratch org with my domain', async function() {
+      this.timeout(1000 * 300);
+      this.slow(1000 * 30);
+      const defaultScratchOrg = await core.Org.create({});
+      const ux = await UX.create();
+      const bf = new Browserforce(defaultScratchOrg, ux.cli);
+      await bf.login();
+      const instanceDomain = bf.getInstanceDomain();
+      assert.notDeepEqual(null, instanceDomain);
+      await bf.logout();
+    });
+  });
+  describe('getLightningUrl()', () => {
+    it('should determine a LEX URL for a scratch org with my domain', async function() {
+      this.timeout(1000 * 300);
+      this.slow(1000 * 30);
+      const defaultScratchOrg = await core.Org.create({});
+      const ux = await UX.create();
+      const bf = new Browserforce(defaultScratchOrg, ux.cli);
+      await bf.login();
+      const lexUrl = bf.getLightningUrl();
+      assert.notDeepEqual(null, lexUrl);
+      await bf.logout();
+    });
+  });
 });