Bugs
  When I open a second file, LT reopens the first sometimes?
  Opening as a web app doesn't allow the icon to be updated.
  The tutorial page has the wrong favicon.
  The favicon has a null type. data:null for favicon is wrong.
  When a line is focused, clicking and dragging the button / input wrapper should be a selection change not a drag. Note's wrapper around input and button doesn't extend up-to button (?) so you miss the edit click. This really stinks for each line because it's jagged with no visual cue.
  An empty line has no cursor.
  Prompt for changelog edits in publish script and maybe move publish script to ~/bin so I can version it.
  Editing a file externally or in the text pane clears the expand state. No idea how preserving expand state will work in the current design without intelligent editor-TextTree diffing.
  When a file starts with empty lines, an empty initial group is created.
  The only way to delete an empty group is the text editor.
  Mobile scrolling is completely broken.
  Test save in Firefox. Shouldn't show it if can't be supported.
  Re-explore columnar scrolling. I think I like this better but it does add a ton of visual noise. Maybe use hover scrollbars.
  Don't include Linear Text in the page title? This repeats for installed web app.
  When I type, the note should stay on screen and not allow the cursor to scroll offscreen as I type.
  There's no way to insert a card at the top of a column easily.
  When I press enter on selected text, delete the selection and split--need unit tests for all this craziness.
  Autosave doesn't support multiple windows. Maybe try to distinguish by filename and error if already present?
  Dragging a line from scrolled location loses the scroll on drop.
  When I reopen Linear Text and attempt to save the last opened file, it doesn't suggest the prior filename.
  When I reopen Linear Text, the local storage contents can be stale even if the last editor was Linear Text because the file handle isn't re-read into local storage.
  Enter at the start of a line does nothing.
  When I highlight text and alt-tab to another window, my highlight is lost.
  When I delete a child's text, and shift-tab to focus the parent, I lose the focus.
File Deno bugs.
  I can't do an exhaustive switch in the default case. `props.page.type satisfies never`
  html and css template strings aren't formatted.
  Some imports are pulled in from the Deno cache and never should be.
  `npm:<package>/path` imports aren't suggested and the error message is confusing when these aren't aliased correctly in the import path.
  Really need declare module support for representing bundling assets without hacks.
  tools/build import auto-removal is erroneous.
  Saving doesn't automatically add or remove imports like normal TypeScript.
  Closest deno.json isn't used for import map or anything. These are available with quickfix though.
  Deno doesn't auto-enable when deno.json is found. Prettier plugin does and it works great.
  tools/build shebang ignored and read as JavaScript.
  Markdown table in readme isn't the correct width.
  unsaved favicon doesn't align perfectly to saved because SVG is used. Just use old png.
Fix CI builds and generate a next release.
I want a way to delete or add cards by clicking, including deleting groups and sub-lines.

Design
  Fix large pixelated favicons.
  Take another pass at (small) realistic notes?
  Expand/collapse button should support a toggle state visually.
  Fix colors to be a consistent scheme. Everything is black and white except what you have created. Fix manifest.json themes too.
  Experiment with white noise background.
  I think for deleting, resurrecting the recycle bin would be nice.
  Text editor slideout could be a lot nicer with a friendly knob.
  Reconsider columnar scrolling. The grid scrolling has me in deep space.
  Toolbar buttons should look a bit nicer. Not distracting like FigJam but maybe square.
  Fix button title hover styles.
  Try to tighten things up so the app feels special.
    Ask me questions about the design.
  Explore custom hand grip cursor like miro https://css-tricks.com/using-css-cursors/#aa-using-a-custom-cursor-to-enhance-an-element
    https://ux.stackexchange.com/questions/52503/who-created-the-mac-mickey-pointer-cursor
    https://ux.stackexchange.com/questions/52336/why-is-the-mouse-cursor-slightly-tilted-and-not-straight#52338
  Add screenshots to manifest.
  What to do about loading prior file but not actually reading it from disk? User could replace the latest with some old copy by mistake.
Dragging
  Clean up drag-line and add interfaces for card interactions.
  Study how drag parenting works in VS Code. I think you have to have a parent and the root is just "insert below me".
  Allow child to reparent siblings (drag b to a)?
    a
      b
      c
    Missing this feature really sucks for single-child parents.
  Very lightly transition column widths so they don't appear to jitter.
  Support group dragging.
  When I press escape during a drag, it cancels the drag.
Prompt to save unsaved work on new file, load file, or page departure.
Improve note editing input.
  Join on backspace? What to do about children? I guess they reparent like in file.
  New group on enter in an empty line.
  back/space: un/indent. Tab is used for focus and spaces indent in a real file.
    Space at the start of a line indents, backspace at the start of a line unindents.
  alt-down to toggle expand / collapse.
  Enter in an empty line creates a new group.
Add ?tutorial query param mode.
How can I unit test the UI effectively? I think the line-input especially needs to be tested for correct effect dispatching.
Plan text editor.
  It feels like this should be a first-class part of Linear Text, not a developer mode.
  Do I want a more featureful editor like CodeMirror? I think so.
    See if they offer a multi-file example.
  What would implementing a minimal editor look like?
    I could explore contenteditable with text nodes on the newline.
    I could change a single line instead of the replacing the entire contents.
    I could reuse my tree structure.
    I could focus the active line in both the editor and the board.
  Consider wrapping. When arrowing left, the cursor is nearly cut off.
  alt-up/down to move lines.
  Shortcuts
    ctrl-c: copy focused but deselected line.
    crtl-x: cut focused but deselected line.
    alt-up/down: move focused line.
    shift-/tab: un/indent selection / line.
  Highlight focused line.
  Show whitespace.
  Any edits you make anywhere can be undone from the editor.
  Bugs
    Pressing enter changes scroll position.
    Weird whitespace injection. Also, pressing backspace seems to unindent.
    Undo doesn't work after deleting a line.
      Can undo-redo be implemented on the editor using document actions like exec and I just wire a button to that?
Support multiple files.
  Workflow wanted: plan.text and schedule.text are open. I copy and paste the day's group into plan.text.
  Think about how the editor works with multiple files.
Keyboard shortcuts
  Keys currently use alt-style access keys for buttons. They also steal focus. This is confusing.
  Shortcuts should be OS-localized.
  Toggle editor.
  Double-clicking an empty group also creates a newline.
  Alt-shift-left to move a group.
  ctrl-tab / ctrl-shift-tab jumps by group.
Autosave on throttled input.
Session backup.
  I think this will require a separate dialog where you can view the past sessions, delete them, open them in recovery read-only mode (doesn't itself modify session data).
  The format needs to be text in case something is broken. You should be able to click a button to copy the entire session too.
How should groups and nested lines support deletes through UI?
  The current approach to delete a line is to clear all the text.
Improve performance.
Docs
  Add bug report link.
  Embed a playground on docs page to fool around with. This wouldn't replace the one at https://lineartext.com.
  Verify line / card terminolgy is used consistently and not confusing in tutorial.text.
  Document non-/technical decisions.
    Custom drag-and-drop over native.
      native is like 30 lines and does a lot well: ~/work/web/linear-text-protos/linear-text-proto-ui-drag-2023-11-13/index.js
      native drag needed weird drag "wings" in one of my protos with nested scrolling to work
      Ability to customize the drag image is limited to an actual image. I had weird issues with the edges being a couple pixels too small, horribly clipped when part of the card was off the screen, and I think sometimes issues with transluency.
      Native implementation is tiny, supports auto-scrolling, supports off-screen movements.
    EBNF for line parsing, lines

Review ~/work/notes/linear-text.
Support linear Markdown. Anything that has a good single-line representation.
  Headings, italics, bold, code, bullets, ...?
  Docs
    Beside what's covered by previews, linear markdown is supported. For example, _italics_, `code`, *bold*, [links](https://oidoid.com), and bullets.
    You can add a one-line JavaScript program by starting a line with `js```.
      js`alert('hello world!')`
    Any markdown that renders as something beside plaintext is editable on hover only (or in the advanced text editor).
    Linear Text encourages a lighter (and more limited) text format than Markdown. Indenting creates a list so you don't need to use bullets for lists unless you like to.
Support images.
  Template strings like CSS: polaroid`file://blah.png`.
  Support file://, http://, and https:// protocol at least.
Support context menu.
  Copy or cut group, card, or card + all children.
  Paste as children or new group. I want to right click on the grid and be able to paste an entire text file in somewhere.
Support URL previews.
  URLs show as previews. For example, https://oidoid.com.
  URLs to images are shown as instant film. Loading lines of URLs is a nice way to show a gallery.
  Images can also be shown as data URIs like data:
  Previews can be explicitly selected like film`https://oidoid.com/logo.png`. The text before and after a preview decorate the header and footer.
  file: protocol is understood as well. Absolute paths are understood and paths relative a loaded file are understood for loaded files only.
Link URLs.
  Support ctrl-click.
  Note sure how to implement this in plaintext contenteditable.
  Add 'noopener,noreferrer'.
  Heuristics for URLs ending in .jpeg, .gif, .png, .webp, .mp4, etc.
Support linking to other files.
  It'd be neat to link to other docs, like a table-of-contents, or open a folder.
Reconsider plain web components
  A template parser like https://github.com/dchester/yhtml/blob/main/example.html.
  ~/work/web/linear-text-protos/linear-text-proto-lit-html-web-components-2023-12-08/src/index.ts
  I don't even make use of the shadow DOM. It just adds complexity.
Explore competitors and technical docs.
  Trello
  Kinopio
    When I click an image, the source becomes editable.
  FigJam
  Nullboard
    Review the tutorial text too.
  Dragula
  tldraw
  https://www.sketch.com/apps
  Review Lit docs.
Built-in search that auto-expands cards.
Support shareable URLs (load by query fragment)?
Toggle expand/collapse-all button.
Explore more card types.
  /home/user/work/web/linear-text-prototypes/perfect-notes-last-proto/docs/oid-ideas.csv
ctrl / shift-click select cards for dragging / delete.
Idea: add @2020-01-02-snooze/reveal to hide a card until a date. Might be some other date-based actions like @2020-01-02-highlight. Or maybe `// hide me` makes more sense for plain text. Not sure how this doesn't get super out of sync though when dragging around.
  I love the idea of timer cards like @2024-01-02 or @12p that ding and light up. The UI has a ton of flex to represent these differently but essentially you get pomodoro cards.
When I copy-and-paste multiple lines, these should appear across multiple cards instead of concatenating on one.
When I divide a card with children, the new card should get the children (just insert above) unless it's collapsed.
Need a lot more unit tests for line parsing, particularly on indentation parenting and moving / reparenting.
Persist file handle and permissions.
  https://developer.chrome.com/blog/persistent-permissions-for-the-file-system-access-api
  https://web.dev/articles/origin-private-file-system
i don't do a lot between columns in linear at least for planning. should thye be wider?