Description of the Issue

After creating and saving new *.R file, further modifications are not being saved! Neither in the c:\Users\Tomas\AppData\Roaming\Notepad++\backup\ directory, and not even when saved explicitly by Ctrl-S! Status of the file (the color of the disquette icon on the tab) is not updated.

Steps to Reproduce the Issue

1. Open new tab by Ctrl-N
2. Write some R code, e.g. "a <- 1"
3. Save as "a.R".
4. Add another line of code, e.g. "b <- 2".
5. Save by Ctrl-S.

Expected Behavior

In step 4, status of the file should update (disquette icon on the tab should turn red). After few seconds, the modified file should be seen in c:\Users\Tomas\AppData\Roaming\Notepad++\backup.

In step 5, changes should be saved in the file "a.R".

Actual Behavior

In step 3, first version of the file is saved successfully, which is allright.

But in step 4, status of the file doesn't update! (Disquette icon on the tab stays blue, doesn't turn red). No changes saved in the c:\Users\Tomas\AppData\Roaming\Notepad++\backup\ directory.

In step 5, no changes are saved in the file "a.R"!!

Notes

• Doing the same process with "*.txt" file shows no such problems.
• It is only problem for newly created files. If I close the file and open it again in NPP, the problem disappears.

Debug Information

Notepad++ v7.9.1 (32-bit)
Build time : Nov 2 2020 - 01:03:56
Path : C:\Program Files (x86)\Notepad++\notepad++.exe
Admin mode : OFF
Local Conf mode : OFF
OS Name : Windows 10 Enterprise (64-bit)
OS Version : 1803
OS Build : 17134.1845
Current ANSI codepage : 1250
Plugins : mimeTools.dll NppAutoIndent.dll NppConverter.dll NppExport.dll NppTextFX.dll SessionMgr.dll

There is 1.6 GB of free space on the disk.