Multiple Browsers — Test 2

Correct Answer: A. The browser may store the response but must revalidate it with the server before each use
Explanation: no-store is the directive that forbids storing the response at all. This is a classic trap. ALSO KNOW (related points): • Which keyboard shortcut performs a hard reload, bypassing the cache, in Chrome or Firefox on Windows? → Ctrl + Shift + R (or Ctrl + F5) • What is the difference between the HTTP cache and the Cache Storage API? → The HTTP cache is managed automatically by the browser from headers; Cache Storage is controlled by code, typically in a service worker

Correct Answer: C. Ctrl + Shift + R (or Ctrl + F5)
Explanation: Ctrl + Shift + N opens an Incognito window in Chrome.

Correct Answer: A. Parse HTML into the DOM and CSS into the CSSOM → build the render tree → layout → paint → composite
Explanation: Changing an element's geometry triggers layout (reflow). Changing only its color triggers repaint.

Correct Answer: D. Changing an element's width
Explanation: visibility: hidden keeps the element's space, so no layout recalculation is needed. ALSO KNOW (related points): • Which image format is widely supported by all major browsers and usually gives smaller files than JPEG or PNG? → WebP

Correct Answer: C. defer runs scripts in document order after the HTML is parsed; async runs each script as soon as it downloads, in any order
Explanation: Use defer for scripts that depend on each other or on the DOM.

Correct Answer: C. No; it runs on a single main thread with an event loop, and Web Workers provide background threads
Explanation: Long-running scripts block the user interface. ALSO KNOW (related points): • Which web font format is the most efficient and universally supported in modern browsers? → WOFF2

Correct Answer: A. It keeps a snapshot of the page in memory so that back and forward navigation is instant
Explanation: Pages using certain features, such as an unload handler, can be excluded from bfcache.

Correct Answer: C. 16px
Explanation: This is why 1rem = 16px by default.

Correct Answer: B. A missing or invalid DOCTYPE declaration
Explanation: In quirks mode, browsers emulate old non-standard behavior, such as an IE-style box model. ALSO KNOW (related points): • What is the default root font size in major browsers? → 16px

Correct Answer: C. It is multi-process, with separate renderer processes (site isolation), so one crashed tab does not crash the whole browser
Explanation: Chrome's own Task Manager (Shift + Esc) shows the individual processes.