If you copy a text from a web page which includes some character style (fonts, colors...) and you paste it in Writer, you get a text with similar style.
If you make the same experiment in Impress you get plain text in the best case. Neither using paste special you can get to copy the styles if they come from HTML.
If you copy from a code editor (like kate or notepad++), to retain code syntax highlight using HTML copy, you have the same problem.
Workaround: copy from anywhere and paste to Writer, then copy from Writer and paste in Impress.
Steps to Reproduce:
1. Using firefox go to this web: https://www.w3schools.com/html/html_styles.asp
2. Copy the lines: I am Red, I am Blue, I am Big.
3. Paste them in impress.
4. Paste them in writer.
5. Observe the difference.
The pasted text in Writer retain the style, but the text in Impress doesn't retain the style. Neither using paste special you can retain the style in Impress.
A way to retain the style of the pasted text in Impress.
User Profile Reset: No
I'm using KDE.
User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:59.0) Gecko/20100101 Firefox/59.0
Arch Linux 64-bit
Build ID: 5956828c88501ef1366e60010b05053a8e1e642e
CPU threads: 8; OS: Linux 4.16; UI render: default; VCL: kde4;
Locale: fi-FI (fi_FI.UTF-8); Calc: group
Built on May 23rd 2018
Arch Linux 64-bit
Version 184.108.40.206 (Build ID: e183d5b)
Version: 220.127.116.11.alpha1+ (x64)
Build ID: 8fae8a6cd73b7262c3739bd4acc5c72b54934ff1
CPU threads: 4; OS: Windows 10.0; UI render: default;
TinderBox: Win-x86_64@42, Branch:master, Time: 2018-05-22_22:52:50
Locale: fi-FI (fi_FI); Calc: group
Same problem if paste in a Text Box of writer.
The problem affects to the whole system. Paste with format does not work in Text Boxes.
The bug still is present in 6.4.2.
Correcting earliest version