[PROPOSAL] New editing mechanism for small screens

[Kureev]

Explanation of Change

Adapt message editing behavior based on screen size to match Slack-style UX. On narrow layouts, editing now uses the main bottom composer instead of inline editing inside the message list, preventing layout shifts, disappearing headers, and scroll jumps. On wide layouts, the existing multi-inline editing behavior is preserved.

Fixed Issues

$ #64085
PROPOSAL: #66240 (comment)

Tests

1. Open a chat on a small screen.
2. Long-press any message and select Edit.
3. Verify the message remains visible in the list and the bottom composer is populated with the draft.
4. Start editing a different message and verify the previous edit is cancelled and replaced.
5. Send the edited message and verify the original message is updated, not duplicated.
6. Repeat the same flow on a large screen and verify inline editing still works.
7. Verify message headers, reactions, and highlighting remain visible during edit.
8. Verify no layout jump or scroll repositioning occurs on mobile.
9. Verify no console errors appear.

• Verify that no errors appear in the JS console

Offline tests

1. Go offline.
2. Start editing a message on a small screen.
3. Verify the draft is preserved in the composer.
4. Go back online and submit the edit.
5. Verify the original message updates correctly.

QA Steps

Same as Tests.

PR Author Checklist

• I linked the correct issue in the ### Fixed Issues section above
• I wrote clear testing steps that cover the changes made in this PR
  • I added steps for local testing in the Tests section
  • I added steps for the expected offline behavior in the Offline steps section
  • I added steps for Staging and/or Production testing in the QA steps section
  • I added steps to cover failure scenarios (i.e. verify an input displays the correct error message if the entered data is not correct)
  • I turned off my network connection and tested it while offline to ensure it matches the expected behavior (i.e. verify the default avatar icon is displayed if app is offline)
  • I tested this PR with a High Traffic account against the staging or production API to ensure there are no regressions (e.g. long loading states that impact usability).
• I included screenshots or videos for tests on all platforms
• I ran the tests on all platforms & verified they passed on:
  • Android: Native
  • Android: mWeb Chrome
  • iOS: Native
  • iOS: mWeb Safari
  • MacOS: Chrome / Safari
  • MacOS: Desktop
• I verified there are no console errors (if there's a console error not related to the PR, report it or open an issue for it to be fixed)
• I verified there are no new alerts related to the canBeMissing param for useOnyx
• I followed proper code patterns (see Reviewing the code)
  • I verified that any callback methods that were added or modified are named for what the method does and never what callback they handle (i.e. toggleReport and not onIconClick)
  • I verified that comments were added to code that is not self explanatory
  • I verified that any new or modified comments were clear, correct English, and explained "why" the code was doing something instead of only explaining "what" the code was doing.
  • I verified any copy / text shown in the product is localized by adding it to src/languages/* files and using the translation method
    • If any non-english text was added/modified, I used JaimeGPT to get English > Spanish translation. I then posted it in #expensify-open-source and it was approved by an internal Expensify engineer. Link to Slack message:
  • I verified all numbers, amounts, dates and phone numbers shown in the product are using the localization methods
  • I verified any copy / text that was added to the app is grammatically correct in English. It adheres to proper capitalization guidelines (note: only the first word of header/labels should be capitalized), and is either coming verbatim from figma or has been approved by marketing (in order to get marketing approval, ask the Bug Zero team member to add the Waiting for copy label to the issue)
  • I verified proper file naming conventions were followed for any new files or renamed files. All non-platform specific files are named after what they export and are not named "index.js". All platform-specific files are named for the platform the code supports as outlined in the README.
  • I verified the JSDocs style guidelines (in STYLE.md) were followed
• If a new code pattern is added I verified it was agreed to be used by multiple Expensify engineers
• I followed the guidelines as stated in the Review Guidelines
• I tested other components that can be impacted by my changes (i.e. if the PR modifies a shared library or component like Avatar, I verified the components using Avatar are working as expected)
• I verified all code is DRY (the PR doesn't include any logic written more than once, with the exception of tests)
• I verified any variables that can be defined as constants (ie. in CONST.ts or at the top of the file that uses the constant) are defined as such
• I verified that if a function's arguments changed that all usages have also been updated correctly
• If any new file was added I verified that:
  • The file has a description of what it does and/or why is needed at the top of the file if the code is not self explanatory
• If a new CSS style is added I verified that:
  • A similar style doesn't already exist
  • The style can't be created with an existing StyleUtils function (i.e. StyleUtils.getBackgroundAndBorderStyle(theme.componentBG))
• If the PR modifies code that runs when editing or sending messages, I tested and verified there is no unexpected behavior for all supported markdown - URLs, single line code, code blocks, quotes, headings, bold, strikethrough, and italic.
• If the PR modifies a generic component, I tested and verified that those changes do not break usages of that component in the rest of the App (i.e. if a shared library or component like Avatar is modified, I verified that Avatar is working as expected in all cases)
• If the PR modifies a component related to any of the existing Storybook stories, I tested and verified all stories for that component are still working as expected.
• If the PR modifies a component or page that can be accessed by a direct deeplink, I verified that the code functions as expected when the deeplink is used - from a logged in and logged out account.
• If the PR modifies the UI (e.g. new buttons, new UI components, changing the padding/spacing/sizing, moving components, etc) or modifies the form input styles:
  • I verified that all the inputs inside a form are aligned with each other.
  • I added Design label and/or tagged @Expensify/design so the design team can review the changes.
• If a new page is added, I verified it's using the ScrollView component to make it scrollable when more elements are added to the page.
• I added unit tests for any new feature or bug fix in this PR to help automatically prevent regressions in this user flow.
• If the main branch was merged into this PR after a review, I tested again and verified the outcome was still expected according to the Test steps.
• If new assets were added or existing ones were modified, I verified that:
• The assets are optimized and compressed (for SVG files, run npm run compress-svg)
• The assets load correctly across all supported platforms.

Screenshots/Videos

Android: Native

Android: mWeb Chrome

iOS: Native

iOS: mWeb Safari

MacOS: Chrome / Safari

MacOS: Desktop

[melvin-bot]

@suneox Please copy/paste the Reviewer Checklist from here into a new comment on this PR and complete it. If you have the K2 extension, you can simply click: [this button]

[github-actions]

Code Review Summary

I've completed a comprehensive review of this PR. The implementation adapts message editing behavior based on screen size, using the bottom composer for narrow layouts and maintaining inline editing for wide layouts.

Key Findings

✅ Strengths:

• Clean separation of narrow/wide layout behavior
• Proper integration with existing draft management system
• Maintains backward compatibility for wide layout users

⚠️ Areas for Improvement:

Several inline comments have been posted with specific suggestions. The main areas of concern are:

1. State management - Multiple useOnyx calls fetching the same data across components could be optimized
2. Edge case handling - Some scenarios around draft cleanup and concurrent edits need consideration
3. Performance - useMemo dependencies and effect triggers could cause unnecessary re-renders
4. Code clarity - Some complex logic could benefit from helper functions or better naming

Testing Recommendations

Beyond the test plan provided:

• Test rapidly switching between editing different messages on mobile
• Test editing while composing a new message
• Test behavior when switching from narrow to wide layout mid-edit
• Verify draft persistence across app restarts on mobile

Overall, this is a solid implementation that addresses the UX issues with inline editing on mobile. The inline comments provide specific suggestions for improvement.

[codecov]

Codecov Report

❌ Looks like you've decreased code coverage for some files. Please write tests to increase, or at least maintain, the existing level of code coverage. See our documentation here for how to interpret this table.

Files with missing lines	Coverage Δ
src/pages/home/report/PureReportActionItem.tsx	52.40% <100.00%> (+0.46%)	⬆️
...report/ContextMenu/BaseReportActionContextMenu.tsx	0.00% <0.00%> (ø)
src/pages/home/report/ReportActionsList.tsx	78.44% <50.00%> (-1.14%)	⬇️
...ges/home/report/ContextMenu/ContextMenuActions.tsx	0.77% <0.00%> (-0.07%)	⬇️
...omposerWithSuggestions/ComposerWithSuggestions.tsx	56.45% <65.71%> (-1.91%)	⬇️
...report/ReportActionCompose/ReportActionCompose.tsx	66.79% <53.12%> (-2.07%)	⬇️
... and 77 files with indirect coverage changes

[Kureev]

Simulator.Screen.Recording.-.iPhone.17.-.2025-12-05.at.11.09.48.mov

[mountiny]

@Kureev I think you have linked wrong issue

Can you please post videos of the behaviour before and after this change with clear explanation of what the changes are so the design and product team can discuss this?

[suneox]

Oops, I lost track of this one so I’ll catch up on the context and review it later today. Currently, we still have a conflict on this PR.

[suneox]

@Kureev Hi! I notice this PR references fix issue #63871 (16KB memory pages) but the changes seem to be about message editing UI (which matches issue #64085).

Can you clarify if:

• This PR should reference issue 64085 instead?
• Or if there's some connection between message editing and 16KB that I'm missing?

The proposal link points to PR 66240 which is about the same UI editing issue.

[suneox]

@Kureev We have an issue where multiple message items cannot be edited, and after submitting all changes, the editing highlight still appears on the edited message.

Before

CleanShot.2025-12-12.at.01.14.14.mp4

After

CleanShot.2025-12-12.at.01.12.01.mp4

[suneox]

@Kureev There is still a conflict on this PR, along with feedback on the remaining issue.

[Kureev]

Hi all, sorry, was on a holidays, will look into it today

[Kureev]

I fixed the merge conflict with the main, currently addressing the aforementioned issues with multiple edits

[joekaufmanexpensify]

@Kureev @suneox what are next steps here?

[suneox]

@Kureev @suneox what are next steps here?

We’re still waiting for @Kureev to handle this issue.

[chrispader]

@suneox i'm going to take this over from Alexey. I'll hopefully be able to address this later today, otherwise on Monday!