We have a Task Pane Add-In for Excel Online.
Installing the Add-In from the Office Store open the sidebar with our IFRAME as expected.
But when we close the tab with the spreadsheet and reopen the same workbook (for edit or not) later, only an icon appears on the right border. Sometimes this is our Add-In icon, sometimes it is a neutral icon (mouse over Office-Addin). Clicking on the icon does not show the sidebar (although it has been loaded). Pressing the arrow above the icon(s) does not help either.
The same thing happens with other Task Pane Add-Ins.
Sometime we can insert our Add-In again (and it works then), sometime we can't (ie we are allowed to insert it, but the UI does not change).
The behavior can be reproduces on Chrome 47, Firefox 41 and Edge.
Whats wrong there?
Thank you for posting this issue and giving us the opportunity to find a resolution. It looks like we are having a temporary issue at present where the Office Addins width is getting saved to 3 pixels. We are striving to find a resolution as soon as possible. In the mean time you can try the following workaround
Temporary workarounds:
After the file is edited in client or excel client, excel client respects the new value and it do NOT go back to value
We will update the article once it is fixed
Thanks Keith
Microsoft Snr Engineer.
I'm delighted to say that the fix for the Excel Add-In issue should be live on Wednesday 4th of November at the latest.
We really appreciate you taking the time to post the question as it has directly resulted in the fix.
Thanks
Keith
Microsoft Snt. Engnieer