Set a consistent browser viewport for Selenium tests to avoid layout-dependent failures and mobile-versus-desktop behavior differences.

Rails console fails after upgrading Ruby because spring tries to load a missing irb file. Updating binding_of_caller to 0.8.0 restores console startup.

Chromedriver logging helps diagnose Selenium Chrome test failures by recording driver activity to a file or terminal. Service configuration or a manually started driver can enable verbose output.

isolator raises errors for non-rollbackable side effects inside DB transactions, such as HTTP calls, queued jobs, and emails.

AngularJS directive lifecycle hooks control template mutation and link-time behavior before and after child directives run, enabling DOM customization and coordinated initialization.

Convert .scss files to indented Sass syntax from the command line with sass-convert, including whole directories.

Generates a complete favicon set for browsers, mobile home screens, and Touch Bar use from a square SVG or image.

Whitespace can disappear in Haml-rendered pages in staging or production, causing inline elements like buttons to stick together. A helper can make intended spacing explicit.

Legacy data can be imported into a new Rails app by connecting a second database and mapping old tables and columns with Active Record models.

Combine multiple PDF files from the Linux command line with pdftk or pdfjam; convert works too, but often lowers quality and increases file size.

IE11 drops calc() inside the flex shorthand, breaking layouts that need percentage widths with gutters. Using flex-basis separately preserves the intended size.

CoffeeScript class methods use @ on the class definition and can be called from instances through @constructor or the class itself.

Upgrading Clearance can break existing logins when password hashes change from SHA1 to BCrypt, causing BCrypt::Errors::InvalidHash for legacy users.

MariaDB and MySQL version changes can alter query results despite sql_mode; aggregated date queries may switch from strings to Datetime, breaking existing applications.

Webpacker-only Rails deploys can fail on deploy:assets:backup_manifest because capistrano-rails expects Sprockets assets. Clearing that task avoids the missing manifest error.

Capistrano records successful deployments with branch, commit, release ID, and user, letting teams trace who shipped which revision and when.

Quick reference for replacing common jQuery DOM tasks with native browser APIs and handling event delegation gaps without jQuery.

Lost or overwritten files can sometimes be recovered after git accidents or failed undo actions by using RubyMine's Local History.

CSS line-height and vertical-align depend on font metrics and inline formatting, making text and element alignment less predictable than it seems.

Encoded email source can hide the plain HTML markup in Thunderbird. Opening a message in composition mode gives access to the HTML view.

git apply can place a diff onto HEAD, often replacing a rebase-and-merge workflow when reconstructing commits or working from a patch file.