Salesforce chat should be visible by default because Firefox browser has pop-ups enabled.
However, if the form is not displayed, follow the below steps to enable the popups and cookies.
Select the Menu button and select Preferences
Select the Privacy & Security panel. This is where you can view your settings for Enhanced Tracking Protection, which includes cookies.
If Standard is selected, this is the default setting and, except for trackers, all cookies are enabled.
If Strict is selected, either choose Standard or switch to Custom.
If Custom is selected, either uncheck Cookies (this will allow all cookies) or select the setting to only block Cross-site and social media trackers.
3. Close the about:preferences page. Any changes you've made will automatically be saved.
For Salesforce Chat to display on a Safari browser, the cookies and pop-ups should be enabled.
How to Enable Cookies
Click the "Safari" menu
Click the "Preferences" menu item
Click the "Privacy" tab
Choose your preferred Cookies and tracking settings
Close the Preferences window
Unblock pop-ups on Safari Desktop
Click “Safari” in the Apple Menu in the top-left corner of your screen. You will need to be in the Safari app to access this menu.
Then click Preferences. You can also access Safari’s Preferences by using the Command + comma keyboard shortcut.
Click on the Websites tab at the top of the Preferences window.
From the left side-bar, click on Pop-up Windows.
Finally, click the drop-down menu in the bottom right corner of the window and select Allow. This will cause Safari to allow all pop-ups. You can also choose to block all pop-ups or notify you every time they are blocked as well.
Open Opera browser and go to Browser Settings.
In settings choose Privacy & security tab.
Scroll down to the Cookies section and choose the checkbox "Allow local data to be set (recommended)"
How to unblock ads and pop-ups
Opera's Adblocker makes websites load faster and look cleaner by blocking ad scripts. It also includes tracking protection and stops cryptocurrency mining scripts for a secure browser. To enable these security features:
Go to Settings (Alt+P)
Under Privacy protection, toggle off Block ads and surf the web up to three times faster.
Below that, toggle off Block trackers
Launch Google Chrome. Then, touch the triple-dot menu on the upper right corner of the browser.
On Settings, choose Site Settings.
Scroll down and you will get two options; “pop-ups and redirects” and “Ads”. Click on them one by one
If you want to enable the Ad-blocker for Chrome Android, click on them one by one and toggle the button to make it grey.
Under the General section, click the toggle next to Block Pop-ups to disable the pop-up blocker. A green toggle indicates an enabled pop-up blocker.