Bugzilla

**Affected versions**
* 88.0a1(2021-03-24), 88.0b1, 87.0;

**Affected platforms**
* Windows 10, macOS 10.15;

**Steps to reproduce**
1. Launch Firefox, access the Customize page;
2. Drag the Search bar and some buttons in the Overflow menu;
3. Close the Customize page;
4. With the TAB-key press it until reaching the toolbar buttons;
5. Press the Right-arrow key to reach the Overflow menu;
6. Press the Enter key to open the menu;
7.  Press the Down-arrow key to navigate inside the menu;

**Expected result**
* each element is selected, navigation goes as expected;

**Actual result**
* Search bar is skipped;

**Regression range**
* considered "good" the prior implementation which the SearchBox was selected but the focus was locked to actions inside it:
* First bad: [2019-04-15](https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=c77962add953a48bdbcbbcd3d157d63d1267cd8e&tochange=b8f49a14c458f56a6a08e4c177671108e386be3a);
* Last "good": 2019-04-14](https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=ec1f3a922d56e0a9393415872ee1d30c2f895fd7&tochange=b8f49a14c458f56a6a08e4c177671108e386be3a)
* Pushlog: [URL](https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=ec1f3a922d56e0a9393415872ee1d30c2f895fd7&tochange=b8f49a14c458f56a6a08e4c177671108e386be3a); 

**Additional notes**
* attached recording to best illustrate the issue;
* reproducible with Proton prefs both true/false;
* while this is a workaround from the previous variation, there would be an enhancement here on which IF the Search bar is empty [Down-Arrow] keyboard navigation to go through and select the next element from the menu; this as opposed to the current implementation in which with keyboard navigation the TAB key is needed to reach the Search box.

**Affected versions**
* 88.0a1(2021-03-24), 88.0b1, 87.0;

**Affected platforms**
* Windows 10, macOS 10.15;

**Steps to reproduce**
1. Launch Firefox, access the Customize page;
2. Drag the Search bar and some buttons in the Overflow menu;
3. Close the Customize page;
4. With the TAB-key press it until reaching the toolbar buttons;
5. Press the Right-arrow key to reach the Overflow menu;
6. Press the Enter key to open the menu;
7.  Press the Down-arrow key to navigate inside the menu;

**Expected result**
* each element is selected, navigation goes as expected;

**Actual result**
* Search bar is skipped;

**Regression range**
* considered "good" the prior implementation which the SearchBox was selected but the focus was locked to actions inside it:
* First bad: [2019-04-15](https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=c77962add953a48bdbcbbcd3d157d63d1267cd8e&tochange=b8f49a14c458f56a6a08e4c177671108e386be3a);
* Last "good": [2019-04-14](https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=ec1f3a922d56e0a9393415872ee1d30c2f895fd7&tochange=b8f49a14c458f56a6a08e4c177671108e386be3a)
* Pushlog: [URL](https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=ec1f3a922d56e0a9393415872ee1d30c2f895fd7&tochange=b8f49a14c458f56a6a08e4c177671108e386be3a); 

**Additional notes**
* attached recording to best illustrate the issue;
* reproducible with Proton prefs both true/false;
* while this is a workaround from the previous variation, there would be an enhancement here on which IF the Search bar is empty [Down-Arrow] keyboard navigation to go through and select the next element from the menu; this as opposed to the current implementation in which with keyboard navigation the TAB key is needed to reach the Search box.