MySQL text search performance differs sharply between LIKE and FULLTEXT; LIKE stays surprisingly fast on medium datasets, while FULLTEXT benefits from larger vocabularies.

Detecting overflow in an element matters when layout must avoid hidden content and unwanted scroll bars; comparing scrollHeight and offsetHeight reveals whether content exceeds the visible area.

document.activeElement returns the currently focused DOM element and is useful for checking focus state in JavaScript or Selenium tests.

Serve CSS at request time from Sass templates while keeping asset_path, imports, and injected theme colors available. Useful when styles need dynamic values without ERB preprocessing.

Old cronjob management with craken no longer works on Rails 3.2+, so whenever becomes the replacement for deploying rake tasks into cron.

Troubleshooting broken RewriteRule and .htaccess behavior in Apache is easier with RewriteLog and high rewrite logging.

Emerging APIs may reshape how websites and web apps are built and used in 2013, opening new capabilities for developers and users.

Unexpected OPTIONS requests in Firefox often signal a cross-origin call or an http to https switch, where browser preflight checks whether the request is allowed.

Code smells in CSS often signal maintainability problems, from brittle selectors to accidental overrides and hard-to-change styles.

Fire custom DOM changed events with CSS instead of polling or deprecated DOM mutation APIs.

Empty navigation containers get the .navy-empty CSS class in navy 0.5.1+, allowing them to be hidden with display: none.

Legacy Syck YAML files can break compatibility with Psych, especially when escapes make translation files unreadable. A small script can convert them by swapping the parser engine dynamically.

Cards can be marked as repeating so important items return to the top of the deck each Wednesday and are not forgotten.

SearchableTrait was extracted into the Dusen gem, adding tests, documentation, and a cleaner query syntax for Googlesque searches in models.

VirtualBox shared folders can fail with read-only or unreadable-file errors when Guest Additions no longer match the VirtualBox version.

Outdated VirtualBox Guest Additions setups can come from an older ISO, causing version mismatches during install or update. Installing virtualbox-guest-additions-iso supplies the matching image.

Xfce panel setup can be tedious, especially with its configuration UI. A classic GNOME 2 or Windows XP-style layout gives a quick, productive desktop start.

Global keyboard shortcuts in Xfce are split between window management and application launching, which makes them hard to find in one place.

File listings may switch to case-sensitive sorting after a distribution upgrade when locale settings change. Reconfiguring the locale restores case-insensitive ordering in Nautilus and Thunar.

Compiz can cause problems on Xfce, and xfwm4 --replace switches back to Xfce's native window manager.

After an Ubuntu version upgrade, sound output or microphone input can stop working because the wrong PulseAudio devices are selected. Reassign the fallback playback and recording devices in pavucontrol.

Multiple Xfce monitors can share separate task bars, each showing only local windows. One panel per screen and per-monitor window buttons keep task switching isolated.

Xfce multi-monitor setup can be awkward when displays overlap or cannot be positioned freely. arandr or a proprietary graphics driver can fix the layout.

Assign the Print key to xfce4-screenshooter -f in Xfce to capture screenshots quickly; many setups already include this shortcut by default.