pages*: add missing mnemonics (part 2)

[vitorhcl]

• [x] The page(s) are in the correct platform directories: common, linux, osx, windows, sunos, android, etc.
• [x] The page(s) have at most 8 examples.
• [x] The page description(s) have links to documentation or a homepage.
• [x] The page(s) follow the content guidelines.
• [x] The PR title conforms to the recommended templates.

[tldr-bot]

The build for this PR failed with the following error(s):

pages/common/boxes.md:32:47 MD047/single-trailing-newline Files should end with a single newline character
pages/common/boxes.md:1: TLDR009 Page should contain a newline at end of file

Please fix the error(s) and push again.