FlashBlock — Spaced Repetition von Web Inventions

FlashBlock turns your browser into a study gate. When cards
are due, every tab gets covered by a review session — you
can't browse around it until you've cleared the queue. When
nothing's due, FlashBlock disappears.

Originally built for hiragana practice, it scales up well
for vocabulary, definitions, formulas, dates, or anything
else that benefits from spaced repetition.

<strong>Card layouts</strong>
<ul>
<li><b>Flip</b> — show the front, click to reveal, then mark
"I knew it" or "I forgot."</li>
<li><b>Typed</b> — type the answer, get instant feedback.</li>
<li><b>Multiple choice</b> — correct answer plus your own
distractors, shuffled each time.</li>
<li><b>Confidence</b> — for cards you can't easily quiz.
"Confident" or "Not confident" after revealing the answer.</li>
</ul>

<strong>Spaced repetition</strong>

Twelve time boxes from one minute to one year. Correct
answers grow the interval; wrong answers shrink it. The
schedule keeps daily review short and frees you from cards
you've actually learned.

<strong>Organisation</strong>

Categories and tags, both with enable/disable toggles so you
can study one topic without losing the rest. Auto-tags
surface cards with audio or by layout. Per-card and
per-category reset to the start. Configurable max batch size
so reviews don't pile up.

<strong>The blocking overlay</strong>

The block lasts until you've cleared the queue, with a
snooze button (5 minutes to 8 hours) for when you genuinely
need to put it off. New blank tabs while blocking is active
redirect to the review screen too, so you can't escape by
opening a fresh tab.

<strong>Audio</strong>

Optional audio per card, on the front and the back, with a
manual replay button.

<strong>Keyboard-first</strong>

Space flips, 1 and 2 grade, 1–4 picks a multiple-choice
answer. You shouldn't need to touch the mouse during review.

<strong>Storage and privacy</strong>

Everything is stored locally in your browser. No account, no
sync, no analytics, no telemetry, no remote backup. Your
cards stay on your computer until you choose to export them
(the options page has a one-click backup that produces a
file you can re-import or move to another browser).

<strong>Permissions</strong>

The extension needs access to all sites because the blocking
overlay must be able to inject itself into every tab when
cards are due. It does not read, modify, or transmit the
contents of pages you visit.