The workbook someone dropped in the channel is editable where it landed.

Files in a chat are the ones people actually work on, and they are the hardest to keep straight — every edit becomes a new upload with a new name. Our app fixes that: Open in SumOffice in the message menu, the file opens in our engine, and saving writes a new version of the same file in the same room, attributed to whoever edited it. Measured on Rocket.Chat 7.10 through the live interface.

What was measured

The round	A macro workbook and a document with five pictures opened from a channel, edited, saved back as a new version in the same room. VBA byte for byte, pictures byte for byte.
The refusals	Checked on both halves — the app and the bridge — rather than on the happy path only.
One condition	Rocket.Chat Community enables private apps after a free workspace registration (Starter). That is their rule, not ours, and it costs nothing.
What this does not say	The fixture workbook these rounds used asks Microsoft Excel to repair it on its own — so no silent-Excel claim here. See Nextcloud and Seafile.

Setting it up

# the editors and the bridge, behind your TLS address
git clone https://github.com/SumOfficeApp/sumoffice-docker && cd sumoffice-docker/nextcloud
cp env.example .env    # PUBLIC_URL=https://office.example.com
docker compose up -d

# the app: sumoffice-docker, branch integrations, folder integrations/rocketchat
# install it as a private app, then point it at the bridge address

Evaluation is free with no time limit; production is the per-application license. The other systems we measured →

Then

Check my Excel file — what your workbooks rely on.
Tell us your Rocket.Chat version — 7.10 is measured.