CodeFill: Syntax Highlighting for Code

CodeFill is an add-on for Google Docs™ that turns code into highlighted code blocks: a monospace font, each keyword, string, number and comment in its color, on a shaded block.

Highlight code in your document: select the lines of code and press Highlight selection. CodeFill detects the language, or you pick one of 49, from Python, Java, JavaScript, C, C++, C#, SQL and HTML to Bash, Go, Rust, Kotlin, Swift and R. The lines become one block, a line per paragraph, so the code stays text you can edit, copy and search.
Paste a snippet: paste code into the sidebar and insert it as a block after the paragraph your cursor is in.
Your look: light or dark; Roboto Mono, Source Code Pro or Courier New; sizes 8 to 14. Put the cursor in a block to change its look, or to highlight it again after you edit the code.

Plans

Free: your first 10 code blocks in total per Google account, fully highlighted. Highlighting a block again is always free.
CodeFill: $9 once per Google account for unlimited blocks. No subscription. Refunds within 14 days. See the terms.

Open it from Extensions > CodeFill in any document.

Highlighting by highlight.js (BSD 3-Clause License).

Add-on will not open or uses the wrong Google account?