Note: When installing your email signature in Roundcube, you need to use the HTML source code of the email signature.
Open your browser and log in to Roundcube Webmail. At the top right, click the Settings button.
On the left, click Identities, and then from the middle, select your identity.
At the bottom, make sure the HTML signature checkbox is ticked and then click the source code button.
When the source code window opens, paste your email signature source code into the text box provided and click Ok. Then click Save.
Go back into Settings > Preferences > Composing Messages. Under the Compose HTML messages section, make sure “Always” is selected. Click Save.
Your new email signature is now installed! Test it out by composing a new email to make sure it looks correct.