Description:
Working with 5+ documents and 200 page average, with different font colors and highlights... makes Libreoffice use 25% of CPU for hours if not terminated. Sometimes reproducible by just opening them on system, but a constant issue if documents are opened through Recovery Mode.

A weird workaround is to kill tasks at random, until it magically drops to 0% even if closing same writer tasks stabilizes the CPU consumption or not, depending on how lucky you are. Also happens to Calc.exe, but also with writer.exe without any calc.exe opened or vice-versa.

This is a bug, because I can work around and maintain all files opened at 0% cpu.
Already tried disabling OpenGl, hardware acceleration, installing new versions of Libreoffice (for years).
Either closing 1000pages processes, it might only drop to 0% when closing a random 100 page document. Changing the specific large documents have the same output.

Steps to Reproduce:
1. open very large files at the same time (occurs more frequently by Recovery Mode)
2. CPU 25%
3. All files work normally, not a single renderisation or any visible CPU demanding feature, which a simple text editor wouldn't solve in 5 seconds

Actual Results:
CPU works at 25%, doesn't stop until I start randomly killing Writer tasks in the windows taskbar.

Expected Results:
Rendering very large files to a point where I can manage to work with them without abusing my hardware or depending on me playing with the software at every startup before getting to work. After years with LO.

This is possibly fixable because, I have to work everytime I reopen files until they stop consuming CPU. So, I fix this a lot, just don't know why.
By ending tasks, and reopenning them again, I can finally arrive at my initial intention of editing simple text files with annotation features which LO offers and notepad.exe doesn't.


Reproducible: Always


User Profile Reset: Yes



Additional Info:
Version: 6.3.3.2 (x64)
CPU threads: 4; OS: Windows 6.1; UI render: GL; VCL: win; 
Locale: en-US (en_US); UI-Language: en-US
Calc: CL