Regular Spaces

Short explanation

Don't use the “Show spaces” feature on documents that are more than ten pages long.

If you want to see your spaces, use Ctrl-F (Cmd-F on Macs) and type a space: result is much better, and instantaneous.

Long explanation

Google Docs doesn't include any native option to show hidden characters, and thus, the only solution I could use to effectively show spaces has been to replace them with a visible symbol. Unfortunately, this symbol has to be a real one, and replacing all spaces in your document means that once done, your document no longer has any spaces in it.

This affects the general layout, and can have some weird effects in justified paragraphs, where Docs is supposed to add extra fake spaces around your real spaces... which are gone.

This is not the main problem, though...  

Technical challenge

Any regular line of text can easily have 15 spaces. Multiply by 40 lines, and you have 600 spaces. 6,000 for ten pages - which is still fine, but bear in mind, that all these replacements generate re-calculation of line breaks and spacing, in a document where all spaces are gone.

Add the “Highlight Symbols” option to the equation, where Show has to add “begin Highlight” code, insert “▪”, add “end Highlight” code : that's 18,000 codes to replace and insert for ten pages, + re-pagination. Still fine. But for a 100 pages doc, that's 180,000 codes, way too much - probably because Google Docs has to reflow the whole doc upon each single replacement (try it by yourself: perform a search & replace through Ctrl-H or Cmd-H, search spaces, replace with ▪ and click replace all : result is damn slow on long documents, even with the native function)

The 5 minutes limitation

Google scripts have to execute in a 5 minutes time frame. Past this delay, script is interrupted on the server.

This is why Show might seem to crash and abandon you at the 140,000th space replaced, without any message, leaving you with a document where spaces are shown only until page 80.

• • This is why Show extension not displaying spaces by default is intentional.

  • This is why Show warns you when you try to show spaces on a long document.

  • This is why I chose to cancel highlighting of regular space symbol.

So how can I see my spaces?

Unless you have a precise need and a document that is not too long, don't rely on Show for that. Use Google Docs built-in Find function instead : hit Ctrl-F (Cmd-F on a Mac), and type a space : this will highlight all your spaces instantly, without leaving edition mode.

For as long as the Search field on the top right won't be closed, spaces will remain highlighted.

This said, there's probably something I'm missing, as I must say I don't understand the interest of showing spaces in the first place.

One possible interest would be to spot double spaces, or lines of spaces, but Search & Replace (Ctrl-H, or Cmd-F on a Mac) seems like a much better option to me than a visual check.