Do you frequently use keyboard shortcuts? Browser keyboard shortcuts such as Ctrl+T (or Command + T on Mac) to open a new tab and Ctrl+W to close a tab are quite universally standard across all modern browsers, but suppose you don’t like these shortcuts. Maybe you rather have something like Alt+T to close a tab.
If you’re a Firefox user, an add-on called Customizable Shortcuts might be able to help you.
No browser restart is required to install this add-on.
After installing the add-on, open up your Firefox Options/Preferences. You will notice a new tab added called Shortcuts.

Customize your Firefox shortcuts with this add-on
To edit any item, simply double click the appropriate item in the shortcut column or select the item line and click the Edit button on the bottom.

Select the appropriate action and perform your desired keyboard shortcut.
Click OK and try out your new keyboard shortcut! There is also a Reset button to reset the shortcut to the default value.
What do you think of Customizable Shortcuts? Have a different tool (perhaps for a different browser) to suggest? Share with us in the comments.