Frequently asked questions

A small collection of tools built and released by k-wada@Legacy Tools. We make and publish small tools — one at a time — that help just a little in everyday life, business, and engineering.

The tools currently available are free to use. If anything changes, we will note it on each tool’s page.

Japanese, English, and Simplified Chinese. The language is auto-selected from your browser and can also be switched manually from the header on each page.

Supported environments vary by tool. Each tool’s page lists its requirements (for example, Safe Privacy Gate is an extension for Google Chrome).

Every tool finishes its processing on your device (locally) and never sends your input or files externally. For specifics, see each tool’s page and our Privacy Policy.

No. The tools themselves never collect or store personal information. The only thing saved on your device is each tool’s settings. See our Privacy Policy for details.

All of the tools work inside the page, so this item appears on their Chrome Web Store listings (the scope differs per product). It is needed to run pre-send checks, show confirmation dialogs, and display results on the page — page content is never transmitted, stored, or collected.

No. All checks run inside your browser and nothing is sent externally.

No. It is only read momentarily for the check and is never stored.

No. It is a helper that prompts awareness — the final decision is yours.

It is a lightweight personal check tool. It does not perform organizational monitoring or enforcement.

No. It never blocks the send — it only replaces your target fields on-device beforehand. Whether anything goes out is up to your action.

No. Detection and masking all run inside your browser and nothing is sent externally.

Major AI chats are covered automatically. On other sites, register the fields you want replaced and it will run there.

No. There is no cap on the count, though many rules or heavy regex may affect processing speed.

No. It only reads and displays — your file stays byte-for-byte identical. There is no feature that removes or strips metadata.

No. All reading finishes on your device, with zero network communication. A CSP forbids network connections, and a build-time check confirms there is no networking code.

No. It never stops or interrupts your send. It only shows a review card; your upload continues as usual.

No. The only inputs for the check are the time of day and your settings — it never reads your message.

No. It only adds a single confirmation. Choose “Send anyway” and your email goes out as is.

It currently supports Gmail (mail.google.com) only, and acts only during the night hours you set (default 22:00–06:00). During the day it does nothing.

No. It reads only the URL and visible text of the link you click, and discards them as soon as it has derived the destination.

No. It shows the real destination and format-level cautions, and never declares a link “dangerous” or “safe.” Whether to open it is always your decision.

No. After “Allow this time,” click the link once more and it opens as usual. It never opens automatically because the final click belongs to you.

Gmail, Outlook on the web, and Yahoo! Mail (Japan). You can also add any webmail domain under “Sites to check” in the settings.

No. It reads only the range of text you selected — never the page’s body, headings, or URL. Even that selection is discarded as soon as it has decided whether the text is a date.

Only inside your browser (chrome.storage.local). They are kept out of synced storage, so they never travel to your other devices.

No. It shows the ordinary age, the Japanese era year, the weekday, and the distance from today — nothing else. It never annotates every date on a page automatically, either.

No. Dates before 1868 (Meiji 1) are not read. Japan used a lunisolar calendar before then, so mapping a Gregorian date onto a Japanese era year would print a day that never existed.

No. It handles only the text you explicitly added from the right-click menu. Because no content script is injected and no host permissions are requested, there is no mechanism for it to scan a page at all.

Only whitespace and line breaks. It removes awkward line breaks and trailing spaces and rejoins wrapped lines inside a paragraph. It does not summarize, rephrase, or proofread, and nothing changes until you press apply.

No. They are kept alongside each item but are not part of the output by default. Turn the page name, URL, and date added on individually when you want them.

No. It is stored in chrome.storage.local only; chrome.storage.sync is not used. You can delete a single item or clear everything at any time, from the popup or the settings tab.

No. It never accesses a value, files, the selection or the clipboard. A build-time check confirms mechanically that none of those appear in the code that handles fields.

No. It makes no safety judgement. It tells you what the page states and what it does not. It does not prove that a company exists, and it does not verify that the statements are correct. Finding nothing does not mean a site is safe.

No. It reads only the page you have open. Something is shown as “Other page” solely because you yourself visited that site’s legal notice, terms, privacy policy or company page earlier in this session.

No. It appears only when you press the toolbar icon. It subscribes to nothing on the page — no clicks, no Tab, no focus changes — so nothing the page does can bring it up. Run it as often as you like; neither running it nor closing it is stored.

You can reach us through the email form on the Support page.

This is run by an individual, so we work through requests in order as we can. Some inquiries may take a little time.

Each tool’s page documents its features and specs in detail. Open “Tools” in the header to browse them.