While the previous answer was helpful in navigating me towards a solution, it focused on Python, and I needed to tackle the issue using Java which presented its own set of challenges. Currently, I am working with selenium version 2.25.0.

//Ensure that the necessary import statements are included - I had to insert these
import org.openqa.selenium.Capabilities;
import org.openqa.selenium.remote.RemoteWebDriver;

WebDriver driver = new FirefoxDriver();

Capabilities caps = ((RemoteWebDriver) driver).getCapabilities();
String browserName = caps.getBrowserName();
String browserVersion = caps.getVersion();
System.out.println(browserName+" "+browserVersion);

For those on Chrome, try the following:

driver.capabilities['version']

If you prefer Firefox:

driver.capabilities['browserVersion']

If you are having trouble with driver.capabilities['version'], double check the capabilities settings. The version number may be located under a different key than expected. I encountered a key error on Windows 10 while trying to retrieve the version number using the version key.

To verify the capabilities:

print driver.capabilities

In my case, this method works for Chrome running on Linux:

driver.capabilities['version']

However, for Chrome on Windows 10, use:

driver.capabilities['browserVersion']

Although not directly related to the previous question, this information could be valuable to anyone seeking guidance on how to code a test based on different behaviors exhibited by various web browsers (such as Firefox vs Chrome). I came across this while searching for a similar solution and wanted to share in case it proves helpful to someone else.

If you are using Python and simply need to identify the browser being tested (e.g., firefox, chrome, ie), you can utilize...

driver.name

...within an if statement. This assumes that you have already assigned the web browser being tested to the variable driver. However, if your testing requirements involve multiple versions of the same browser, you may also want to access driver.version. I hope this information proves beneficial to others who may find themselves in a similar situation. The answer I was seeking led me to this thread, prompting me to contribute in case it aids someone else.

To retrieve the browser version of the GeckoDriver initialized firefox session, you can access the capabilities object which provides a dictionary. Here is the code snippet to accomplish this:

from selenium import webdriver
from selenium.webdriver.firefox.options import Options

options = Options()
options.binary_location = r'C:\Program Files\Mozilla Firefox\firefox.exe'
driver = webdriver.Firefox(firefox_options=options, executable_path=r'C:\WebDrivers\geckodriver.exe')
my_dict = driver.capabilities
print("Mozilla Firefox browser version is: " + str(my_dict['browserVersion']))
driver.quit()

The output on the console will be:

Mozilla Firefox browser version is: 77.0.1

Fetching all capabilities

In a similar manner, you can gather all the properties from the dictionary using this code snippet:

from selenium import webdriver
from selenium.webdriver.firefox.options import Options

options = Options()
options.binary_location = r'C:\Program Files\Mozilla Firefox\firefox.exe'
driver = webdriver.Firefox(firefox_options=options, executable_path=r'C:\WebDrivers\geckodriver.exe')
my_dict = driver.capabilities
for key,val in my_dict.items():
    print (key, "=>", val)
driver.quit()

The console will display:

acceptInsecureCerts => True
browserName => firefox
browserVersion => 77.0.1
moz:accessibilityChecks => False
moz:buildID => 20200602222727
moz:geckodriverVersion => 0.26.0
moz:headless => False
moz:processID => 12668
moz:profile => C:\Users\Soma Bhattacharjee\AppData\Local\Temp\rust_mozprofileFc1B08
moz:shutdownTimeout => 60000
moz:useNonSpecCompliantPointerOrigin => False
moz:webdriverClick => True
pageLoadStrategy => normal
platformName => windows
platformVersion => 10.0
rotatable => False
setWindowRect => True
strictFileInteractability => False
timeouts => {'implicit': 0, 'pageLoad': 300000, 'script': 30000}
unhandledPromptBehavior => dismiss and notify

If you need to wrap your WebDriver with EventFiring capabilities, creating a custom implementation of EventFiringWebDriver is necessary.

import org.openqa.selenium.Capabilities;
import org.openqa.selenium.HasCapabilities;
import org.openqa.selenium.remote.RemoteWebDriver;
import org.openqa.selenium.support.events.EventFiringWebDriver;

public class CustomEventFiringWebDriver extends EventFiringWebDriver implements HasCapabilities {

    private RemoteWebDriver driver;

    public CustomEventFiringWebDriver(RemoteWebDriver driver) {
        super(driver);
        this.driver = driver;
    }

    @Override
    public Capabilities getCapabilities() {
        return driver.getCapabilities();
    }

}

I wanted to share this solution as I faced the same issue myself.

If you're a Python user looking to display all the capabilities, I have the answer for you. It's a simple command that gets the job done.

print driver.capabilities

When working with C# Selenium, I implemented the following code:

ICapabilities capabilities = ((RemoteWebDriver)driver).capabilities;
capabilities.GetCapability("browserName");
capabilities.GetCapability("browserVersion");

The code executed smoothly without any issues.