Operating System (e.g. Windows, MacOS, Linux): Windows 10
Browser (e.g. Chrome, Firefox, Safari): Chrome and Edge
Channel (Name of the channel you were working on): EwB Revision 
Description of problem:
For the last 24 hours, I seem to be unable to delete any folders or exercises. I click the checkbox for the resource and then click delete, and nothing happens. I also try clicking on the menu of the resource and then click remove, and nothing happens. I also tried refreshing the page and logged out and in again.
Is there some issue happening on the Kolibri side?
Here are the errors I see in Microsoft Edge Version 101.0.4951.54:
and here are the errors I see in Google Chrome Version 101.0.4951.54:
Hi @nikitab,
We did notice several deletion tasks processing for your channel on Kolibri Studio yesterday. There’s currently a known issue where mass operations can conflict with each other and result in failure. The behavior that you described seems indicative of failure to process some of your deletions.
I’ve loaded your channel in my browser without seeing any of those error messages you’ve shared. I realize you’ve already tried this, but I suggest you sign out and sign back in again. Doing so should clear the channel data stored in your browser. Clearing that data will make sure that your browser and Kolibri Studio’s database are in sync.
If you still see those errors, please share the topic/folder that you’re accessing which causes the errors. As far as deleting your resources, please proceed to do so in small batches over time.
We’re working hard on many fixes to resolve issues like this, and those updates should be released in the next few months.
Regards,
Blaine
Thank you for your quick reply, Blaine! We are so close to having our channel ready!
Here are some more observations, in case they are useful to anyone:
I did a lot of edits, moving resources between folders, deleting resources and deleting questions.
The browser gets slower as I do more edits, so I regularly have to refresh the page for it to regain speed.
After refreshing, I often notice that the number of resources inside a folder is no longer accurate, so I have started logging out and logging in again in order to see the right number of resources.
However, when I did that on Wednesday, most of my latest edits were gone (resources that i have moved or deleted were back). I let it rest for a day and after refreshing, some of my edits were back, but not all.
So it seems that I should give it plenty of time to process after I am done editing before logging out and back in.
Today, I am trying to finish my edits in Edge and it seems that it is faster to load Studio in Edge.
There was a Chrome update this week, so I am wondering if it might have impacted Kolibri?
Regardless, it still gets slower and slower as I do edits until the page eventually crashes, then gets faster after I refresh the page. However, the number of resources shown is not always right.
Looking forward to the future updates!
most of my latest edits were gone (resources that i have moved or deleted were back)
Unfortunately, this is a symptom of these edits conflicting with each other in a way that causes them to fail entirely on Kolibri Studio’s server side. This can happen when moving, copying, or deleting a large number of resources. Please retry them in batches of ~5 topics/folders or resources.
Regardless, it still gets slower and slower as I do edits until the page eventually crashes
We’re aware of this issue as well and we’re actively investigating it. Browsing and navigating large channels can increase memory usage in the browser, causing it to slowdown and crash.
Regards,
Blaine
Hi again,
Maybe related to the issues above:
Last week, I created my own topics and my own exercises. I stayed signed in for a while to make sure everything was processed on the server side, then I signed out of Studio. I just signed in again now and one of my four topics is empty (Grade 6 missing 6 exercises) and one topic (Grade 5) is missing 5 of 8 exercises.
I am going to give it some time and hope that the exercises show up again. Is there anything you can see on your side?
Hi @nikitab,
Sorry to hear that you’ve lost the exercise content. Again, signing out and back in will clear the channel data loaded into the browser, including changes you’ve made which may not yet have synced to the Studio’s servers. I recommended that in regards to your original issue of being unable to delete resources, but in other circumstances, it can lead to data loss.
Regards,
Blaine
Thank you for your reply.
How can we know that the data have synced to the Studio’s servers and that it is safe to sign out?
I routinely have to sign out and in again to see the right number of exercises.
I waited close to 48 hours between my last edits and when I signed out, and I lost 11 original exercises.
Can you please confirm that the exercises are lost and that I have to rewrite them?
If you attempt to close the browser tab in which you have the channel open, it should alert you if you have unsynced changes. Closing the browser tab shouldn’t delete those changes, but if you close and re-open it, wait, then try to close it again and it doesn’t give you a warning, then it should be safe to sign out.
I checked your channel topic and I don’t see any exercises.
Thank you for checking. I do see the warnings sometimes and have started testing when I get the notification or not. For example, when I copy resources from the public channels through the library in Studio and then click the Channels menu to go back to my own channels, I often get the warning that modifications haven’t been saved, which confuses me since I already received the “Copied to clipboard” notification.
However, when I signed out on Sunday, 44 hours after my last edits, I didn’t get a warning and I lost a third of the exercises I wrote. The edits that I did to Khan Academy exercises and lost two weeks ago did take a few hours to come back after I signed back in, however these original exercises haven’t shown back since I logged in on Monday and you confirmed that they are gone. So something different happened this week.
I will rewrite the missing exercises today and then I should be all done with Studio. Thanks again for your replies, they are greatly appreciated!
