If you want to speed up the loading of the login page significantly, you can use the addon "Adblock Plus" to prevent certain resources to be loaded (stylish only hides them).
Add the following blocking rules (can be done all at once):

||img.ui-portal.de/games/$image
||img.ui-portal.de/fallback/$image
||i0.web.de/image/$image
||img.ui-portal.de/cms/webde/produkte/$image
||img.ui-portal.de/homepage/img/webde/icons/footer/$image
||js.ui-portal.de/*/webde/*/homepage.js|


# Update: Removed "Einschreiben" in options when writing email; Removed "Zeitversetzt senden" ad when sending email
# Update: Removed new "specialad" and All-Net button
# Update: Fixed new splash site
# Update: Removed more stuff from the left menu (SMS, Pinwand, Fax)
# Update: Updated RegExp AND fixed issue with waybackmachine.org / archive.org
# Update: web.de changed something with the wrappers, so a little fix was necessary
# Update: Removed "XXL-Speicher" ad when writing email; Changed weather option default to "yes".
# Update: Corrected message on login failed; Removed stuff after sending an e-mail.
# Update: Replaced many domain rules by RegEx; Removed Webcent overlay and flyoutFeatureTeaser; Small code changes regarding hints; Removed some legacy code; Updated screenshots; Added message on Login failed.
# Update: Made rules for splash pages more general (--> fixes webcent splash page), added option to show weather on login screen
# Update: Added linebreaks in the sourcecode to get rid of long lines.
# Update: Added pointless menu option for "ludor" ... (is klar, ne)
# Update: Removed double domain rules.
# Update: Credits added (thanks Norwin), corrections for mailbox on small-width devices added (thanks "Johnny English"), description and name updated, screenshots added, small corrections regarding footer and splash screens as well as collapsed navigation. Corrected login and logout for smaller devices. Fixed horizontal scrollbars at start page.
# Update: Major code changes for more convenience.