Verify Changes with Simultaneous Editors in Collabora Online Calc

Deployment and evidence boundary

Collabora Online Calc in a desktop browser, English interface, editable ODS practice file. Online controls were checked in the vendor’s historical 25.04 branch source at commit 3847fbcfe35a234544cf163ed9e004a3d197337c on 19 October 2026; this historical source snapshot is not a current development head or certification of any hosted build. Record the actual COOLWSD and LOKit versions from Help → About, browser, interface, and storage host before testing. Desktop Collabora Office and mobile apps are outside scope.

The exercise has independently checked synthetic expectations, not a live application result. No current native GUI or authorized hosted test file was available, so native screenshots and save/reopen evidence remain pending. An unavailable, renamed, disabled, or policy-blocked control is a stop condition; do not substitute a desktop-only route. Keep the original safe and work in a disposable file created through your existing authorized host. Host permissions, autosave timing, revision history, and clipboard policy are not established by the Online source.

Use a recorded cell ledger to distinguish a visible collaborative edit from a saved, reopened result. This is a recipe for the workbook owner to carry out with existing authorized test access. It is not a report that two editors were run here.

Required access and starting ledger

You need a disposable hosted ODS workbook and two already authorized editor sessions, A and B, using existing permitted accounts. If this is not already available, stop and obtain access through your normal process. This guide does not ask you to create accounts, send invitations, change permissions, or share a real file. Distinguish the sessions in their browser profiles and confirm both open the same host file, not two downloads with the same name.

Create one sheet named Ledger, with all unlisted cells blank:

Cell	Initial entry
A1	Item
B1	Count
A2	Kits
B2	4
A3	Repairs
B3	6
A4	Total
B4	=SUM(B2:B3)
D1	Resolution
D2	Initial

Save the starting workbook and verify both sessions show B2 4, B3 6, B4 10, and D2 Initial. Record time, file identity, both builds, interface, and host saved-status wording in a separate local test log. Presence indicators help identify participants but do not prove durable saving.

Separate-cell edits

1. Session A changes B2 to 7 and presses Enter, leaving cell-edit mode. Wait until B sees B2 7 and total 13. Record this observation; do not simply assume a fixed propagation delay.
2. Session B changes B3 to 9 and presses Enter. Wait until both show B2 7, B3 9, B4 16. Do not continue if either view differs or a connection warning is present.
3. Request Save using the available Online command. Wait for the host’s successful saved indication and record it. Keep both sessions online for the next step.

Observe a same-cell collision without guessing its winner

Agree in advance that the desired resolved value of B2 is 12. A attempts B2 11 and B attempts B2 12 close together, each committing the edit. Observe whether the application serializes edits, prevents an entry, displays a warning, or briefly shows different results. Record the actual sequence and both displayed values; no universal last-writer, locking, atomicity, or merge policy is claimed here.

Stop both editors from typing. Compare the formula bar and displayed B2 on both sides. An observed 11 would imply total 20; 12 would imply 21. A different result or mismatch is a failed checkpoint, not permission to overwrite other work. Have the designated resolver A explicitly enter B2 12 after B has left cell-edit mode. Then set D2 Resolved to 12. Both sessions must converge on B2 12, B3 9, B4 21, D2 Resolved to 12 before saving again.

Reopen and grow the ledger

Before saving and reopening, record the actual practice filename and its host folder/location or stable file identity in the local test log. Distinguish same-titled files by that host identity; a download is a separate file. After saved status is confirmed, close B normally and reopen that recorded filename at its exact host location or stable file identity. This is a clean reconnect test, not an offline-edit guarantee. B must see the resolved four-cell checkpoint. Keep A open until B has confirmed it. The vendor’s 25.04.13 release notes report a fix for losing the latest cell edit when a tab closes before the edit is finished, so Enter and save/reopen checks are deliberate even on newer builds.

Once both sessions agree, A sets A5 Service, B5 3, and replaces B4 with =SUM(B2:B3)+B5. Both should see total 24. This formula deliberately excludes B4 to avoid a circular reference. Save again, wait for host confirmation, close both sessions, and reopen the recorded filename at the same exact host location or stable file identity.

Final checkpoint: B2 12, B3 9, B5 3, B4 24 with =SUM(B2:B3)+B5, and D2 Resolved to 12. A and B each record the reopened result; if either differs, retain the ledger and escalate to the host administrator before editing further.

Recovery and boundaries

If a connection drops, stop typing, record pending cell/value intentions outside the workbook, and reconnect without assuming queued edits survived. Compare reopened cells with the ledger, then have one agreed resolver re-enter only missing synthetic values after checking the other session is no longer editing. Avoid repairing a shared document or restoring an old revision without reviewing the impact on other people’s changes; host version history is not universally available.

Preserve the final saved workbook before optional reset. Create a separate authorized reset copy with a different filename and record its host location or stable identity. Confirm the reset copy is active rather than the preserved final file. With only one test editor active in that reset copy, clear A5:B5, restore B2 4, B3 6, B4 =SUM(B2:B3), and D2 Initial; verify total 10. Do not rely on Undo after closing or undo another editor’s work.

Personal filtering is a different concern: the existing Sheet View guide tests display isolation. A personal view does not isolate actual cell-value edits. No live multi-editor session, host save acknowledgement, recovery, or screenshot was captured for this manuscript.

Sources and testing disclosure

• Online multiuser Calc test source, not an executed test here
• 25.04 maintenance release notes

Vendor source and documentation were reviewed; synthetic expectations were computed independently. Source-code review is not native application execution. Preserve deployment-specific verification and publication holds. No screenshot is supplied because no matching current GUI capture was available.