Browser fullscreen handling is inconsistent across vendors, forcing boilerplate and event workarounds. screenfull provides a small wrapper for cross-browser fullscreen requests, exit, state, and change events.

Monitor logs across multiple app servers from one terminal and avoid missing per-host errors; LOG selects another file, and terminal line truncation can hide long entries.

Capistrano can hide long command output with ellipses, making deployment logs harder to read. Disabling Airbrussh truncation keeps full server paths and responses visible.

Large JavaScript libraries can be loaded only when needed to keep initial bundles small and avoid duplicate script execution, memory leaks, and repeated event handlers.

Remove selected HTML tags while preserving their inner text and other child nodes using contents() and unwrap() in jQuery.

Rails console debugging for mail delivery failures, with ActionMailer settings inspection and a direct test message to verify SMTP and spam score.

Large PostgreSQL databases can hide tables that consume most disk space. pg_total_relation_size and pg_size_pretty help identify the biggest relations quickly.

Keep Rails or IRB commands available after exit by saving console history to a file and increasing the retained history length.

IRB may warn during boot when an alias conflicts with an existing method in its context, especially in programmatic setups.

Bundler can fail when a gem exposes dependencies missing from the API or lockfile; manually adding them to Gemfile.lock may restore bundle install.

Public file links in email can lose host and port information; combining root_url with a CarrierWave file path keeps contract URLs usable in mailers.

RubyGems 2.5.1 can raise Gem::Package::PathError during installation when the target path is invalid; updating RubyGems with gem update --system often resolves it.

Flexbox and Grid both handle responsive layout, but Flexbox fits one-dimensional arrangements while Grid is built for two-dimensional page structures.

Storing item order in a database is easy with a position column, but moving one item can force multiple row updates; alternative schemas avoid that churn.

expect(...).to receive can handle repeated method calls with the same or different arguments by chaining return values or using ordered expectations.

Running out of space on /boot can block updates on older Ubuntu installs. Resizing it after an encrypted partition requires rebuilding the partition layout without losing the LUKS volume.

Persistent RubyMine warnings can clutter code and hide real issues; unused inspections can be turned off or adjusted to match your workflow.

Cleanup commands for leftover dump files and unneeded local MySQL, MariaDB, and Postgres databases, with whitelisting and flexible authentication methods.

Rails 2 apps can break on MySQL 5.7; MariaDB 10.x is a compatible replacement for old and new applications, with gem rebuilds sometimes needed after switching.

Store a MySQL root password in ~/.my.cnf on a trusted development machine to avoid password prompts for mysql and mysqldump.

httpclient can ship with an outdated custom certificate store, causing SSL verification failures. Using the operating system’s default CA paths keeps trust roots current.

Rails apps upgrading to Cucumber 3 often need gem updates, new tag syntax, and step-definition fixes to avoid parser and argument-mismatch errors.

Expose a class-level answer through instances by delegating an instance method to class with ActiveSupport's delegate.