Long log file prevents Unreal Editor from starting

Build Type: Binary

Build version: 4.16.3-3561208+++UE4+Release-4.16

Description of the issue:
Generally, issue is that Unreal Editor won’t even start, if latest log file is Very long. If Notepad++ won’t open a file due to it’s size, so won’t Unreal.

More detailed description: Every project has it’s logs stored at ProjectRoot/Saved/Logs/ProjectName.log .
Now, every time Editor is started anew, this ProjectName.log file is backed up with creation date appended to the name, and new ProjectName.log file is created.
The issue is, that if ProjectName.log is very large, and Unreal Editor fails to open it, Editor won’t start. And the issue is silent!!! Why does UE try to open the file in the first place, instead of just renaming it?

Screenshots/Link to video: N/A

Repro Steps are easy:

Action 1 Install Sublime Text.

Action 2 Open your ProjectName.log with it, and start copy-pasting random text there. For example do Ctrl+A, Ctrl+c, Ctrl+v untill your file is so big, that nothing except Sublime opens it.

Action 3 Try to start Unreal Editor. Wait forever.

Action 4 ...

Action 5 Profit :)

Issue happens 100% of the time for me.

System Specs:

System: Dell Inspiron 15 7000 Gaming

CPU: Intel(R) Core™ i7-7700HQ CPU @ 2.80GHz

RAM: 16 GB

Graphics Card: NVIDIA GeForce GTX 1050 Ti

DXDIAG: DirectX 12

Hello,

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Thanks