[Awaiting Checklist Completion] [$1000] After going back from a thread, clicking on New Message button doesn't scroll to the new message at the bottom

[kbecciv]

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Action Performed:

1. Open any LONG chat
2. Receive a NEW message (or just mark the latest message as UNREAD)
3. Scroll up the chat list >> Go into any sub-thread
4. Click Back button on Mobile or Browser to go back to the main chat
5. Click on New message button

Expected Result:

It should scroll to the latest/new message

Actual Result:

Clicking on New Message button doesn't scroll to new message at the bottom

Workaround:

Uknown

Platforms:

Which of our officially supported platforms is this issue occurring on?

• Android / native
• Android / Chrome
• iOS / native
• iOS / Safari
• MacOS / Chrome / Safari
• MacOS / Desktop

Version Number: 1.3.32.5
Reproducible in staging?: y
Reproducible in production?: y
If this was caught during regression testing, add the test name, ID and link from TestRail:
Email or phone of affected tester (no customers):
Logs: https://stackoverflow.com/c/expensify/questions/4856
Notes/Photos/Videos: Any additional supporting documentation

Web.mp4

Recording.899.mp4

Desktop.2023.06.25.-.22.20.55.21.1.mp4

Expensify/Expensify Issue URL:
Issue reported by: @tranvantoan-qn
Slack conversation: https://expensify.slack.com/archives/C049HHMV9SM/p1687451519479619

View all open jobs on GitHub

Upwork Automation - Do Not Edit

• Upwork Job URL: https://www.upwork.com/jobs/~0172cbe3d50bd00465
• Upwork Job ID: 1673464192182222848
• Last Price Increase: 2023-07-03

[melvin-bot]

Triggered auto assignment to @twisterdotcom (Bug), see https://stackoverflow.com/c/expensify/questions/14418 for more details.

[melvin-bot]

Bug0 Triage Checklist (Main S/O)

• This "bug" occurs on a supported platform (ensure Platforms in OP are ✅)
• This bug is not a duplicate report (check E/App issues and #expensify-bugs)
  • If it is, comment with a link to the original report, close the issue and add any novel details to the original issue instead
• This bug is reproducible using the reproduction steps in the OP. S/O
  • If the reproduction steps are clear and you're unable to reproduce the bug, check with the reporter and QA first, then close the issue.
  • If the reproduction steps aren't clear and you determine the correct steps, please update the OP.
• This issue is filled out as thoroughly and clearly as possible
  • Pay special attention to the title, results, platforms where the bug occurs, and if the bug happens on staging/production.
• I have reviewed and subscribed to the linked Slack conversation to ensure Slack/Github stay in sync

[twisterdotcom]

I recreated this on desktop too. This is an annoying bug for sure. We must be somehow marking the room slightly as read when entering a thread?

[melvin-bot]

Job added to Upwork: https://www.upwork.com/jobs/~0172cbe3d50bd00465

[melvin-bot]

Current assignee @twisterdotcom is eligible for the External assigner, not assigning anyone new.

[melvin-bot]

Triggered auto assignment to Contributor-plus team member for initial proposal review - @thesahindia (External)

[sabhyap]

Proposal

Please re-state the problem that we are trying to solve in this issue.

After going back from a thread, clicking on New Message button doesn't scroll to the new message at the bottom
What is the root cause of that problem?

What is the root cause of that problem?

In ReportActionsView, the Report.subscribeToNewActionEvent function isn't subscribed after backing from any other screen.

i.e:
When the user add any chat, notifyNewAction function is called for the current chat channel of report id.

When the this newActionSubscriber is subscribed In ReportActionsView, the scrolling works.

App/src/pages/home/report/ReportActionsView.js

Line 102 in 5f5dd02

this.unsubscribeFromNewActionEvent = Report.subscribeToNewActionEvent(this.props.report.reportID, (isFromCurrentUser, newActionID) => {

If the user go to sub-thread, report id of newActionSubscriber in Report.js is updated to report id of sub-thread.
so notifyNewAction function works for sub-thread.

When backing to main screen, report id of newActionSubscriber has to be updated to report id of main screen.
but it doesn't work. so the scrolling doesn't work for main screen.

What changes do you think we should make in order to solve the problem?

We can fix this issue as following:

Report.subscribeToNewActionEvent function move from componentDidMount to Report.subscribeToNewActionEvent.
Report.subscribeToNewActionEvent in Report.subscribeToNewActionEvent is called on following condition.

        if (Report.newActionSubscriber.report !== this.props.report.reportID) {
              this.unsubscribeFromNewActionEvent = Report.subscribeToNewActionEvent(this.props.report.reportID, (isFromCurrentUser, newActionID) => {
                  .....
        }

What alternative solutions did you explore? (Optional)

N/A