storyday

force user login into wordpress only from one browser at the same time 
the last login action will kick out the already logged user 
this is a security plugin for wordpress,install this plugin to avoid simultaneously login

multi-login-checker

force user login into wordpress only from one browser at the same time

Christian Gatti

Login Watchdog is one of the several NutsForPress plugins providing some essential features that WordPress does not offer itself or offers only partially.  
Login Watchdog include these very useful functions for your every-day secure and protection of your WordPress website:
<ul>
<li>Two Factors Authentication for administrators: after a successful login every administrator is asked to enter a validation code sent by email; you can also set an option to skip two factors authentication until IP does not change, which is extremely useful for administrators they need to login frequently from the same IP</li>
<li>Login Attempts Monitor: checks login attempts and blocks (temporarily or permanently) failed login attempts exceeding the limits defined</li>
<li>Daily Check Notification: sends a notification when a difference is found between your site WordPress core files and the original ones of a clean setup, or when other suspect files are found</li>
<li>Security Notification: sends a notification on administrator successful login, on change of role, on plugin activation, on administrator delete and on user temporary or permanent lock down</li>
<li>Disable XML-RPC: disables XML-RPC protocol to prevent brute force attacks</li>
<li>Disable Author Page: hides author archive page and hides user info via API REST, so that none can know the author name by his ID</li>
<li>Custom Login Errors: displays custom login errors instead of WordPress default</li>
</ul>
Login Watchdog is full compliant with WPML (you don’t need to translate any option value)
Take a look at the others <a href="https://wordpress.org/plugins/search/nutsforpress/" rel="ugc">NutsForPress Plugins</a>
Whatever is worth doing at all is worth doing well
<h3>Translations</h3>
<ul>
<li>English: default language</li>
<li>Italian: entirely translated</li>
</ul>
<h3>Credits</h3>
<ul>
<li>Very many thanks to <a href="https://dkr.srl/" rel="nofollow ugc">DkR</a> and <a href="https://sviluppoeuropa.it/" rel="nofollow ugc">SviluppoEuropa</a>!</li>
</ul>

NutsForPress Login Watchdog

NutsForPress Login Watchdog a simple and lightweight plugin that protects your site from unauthorized login attempts.

multi-login-checker vs NutsForPress Login Watchdog