Hi Can you find back at historiacl record?  please add UserSupport into your project, and send a message to me,  I will help to check.

@UserSupport yes, i have 1 record there. I added you to my project -- "twatch_main"

Hi Check your document only one historical, and the file data only one Drawing symbol please check your other project. I believe that you open a wrong project or login a wrong account.

@UserSupport Thanks a lot! I guess i understand what happened. something happened with interface and I can't see schematic (i see my sheet with all elements for other project in preview, but when i open sheet - i see empty page). How can i fix it?  for twatch_main project with one Drawing symbol i guess I deleted sheet (can i recover sheet? i see all history for sheet2 in "Document recovery" but - when call Recovery i see newerending "Loading" window )

The preview window only show the file you click it at the right-side document's title, it will keep previous images before you click a new document. if you deleted the sheet, you can try find it at Recycle Bin, at the bottom-left corner. for this loading window, if you can see the parts in the canvas, you can close the loading window by ESC key, if you doesn't see the parts, that means this sheet can not open correctly, maybe it already crashed.

@UserSupport Thanks again! ) Recycled Bin - helped, I returned my shema-sheet  back. but left 1st question.  I clicked on right-side document's title, i see new preview, i click to open sheet for editing. But canvas still empty and i can't edit shematic. This is crush case? example on my screen 

I can open this document, can you try at browser incognito mode? 

@UserSupport i guess it is really browser (_cache_) problem! I opened project via application and I see all my shematics, and your hint about incognito works too, i see scheme as expected. Thanks a lot for your help!

@kotehoroshij You are welcome, we are glad you open your file.