Hidden Comments
If you add a lot of details to your tasks your note can get cluttered quite fast. The following theme can help by hiding blocks of text where you can add information about a task. Behind the task text (or any kind of paragraph) type your comment enclosed in %%, for example, %%comment%%.

Theme Code
If you have an existing custom theme, you can add the following to your theme file to support this feature:
"comment": {
"regex": "(%%)([^:]{1,})(%%)",
"matchPosition": 2,
"isRevealOnCursorRange": true,
"isHiddenWithoutCursor": true,
"color": "#888888"
},
"comment-left-colon": {
"regex": "(%%)([^:]{1,})(%%)",
"matchPosition": 1,
"isMarkdownCharacter": true,
"color": "#88818475"
},
"comment-right-colon": {
"regex": "(%%)([^:]{1,})(%%)",
"matchPosition": 3,
"isMarkdownCharacter": true,
"isHiddenWithoutCursor": true,
"isRevealOnCursorRange": true,
"color": "#88818475"
},
Or download the full theme file here.
You can import a theme on Mac using the menubar:

This will be automatically synced to your iOS devices. If you are not using a Mac, you can open the Files app on iOS and navigate to "On my iPhone/iPad" > "NotePlan" > "Themes" and move the file to this folder.
Contributions
Thanks to @antony.sklyar for sharing the theme code on Discord.