Pick a length and character sets and get several at once. Option to drop look-alike characters (l·1·O·0).
For a random password, length is strength. 16 characters mixing cases, digits and symbols is roughly 100 bits, beyond realistic guessing with current hardware. 12 is decent; 8 is the bare minimum many services accept.
The browser's crypto.getRandomValues (the operating system's random source), with character selection done without modulo bias. The values exist only on this page and are never stored or transmitted.
Most account takeovers reuse a password leaked from another site. Use a different one everywhere and let a password manager remember them.
Some sites refuse certain symbols. Turn symbols off and add about four characters of length to keep similar strength.
No. They are not recorded anywhere and disappear when you close the page.
Lowercase l, uppercase I, digit 1, uppercase O, digit 0, lowercase o and the vertical bar. It avoids mistakes when writing or reading a password aloud.
Some browser settings block the copy button. Select the text and copy manually.