The text editing for Roll20 can be frustrating. What I found to be easier is to create most of my text including any tables is to create a word document first, save as rich text format. Keep the formatting and fonts simple. After you have saved the document in rtf, ctrl-a to select all, ctrl-c to copy, go to Roll20 text field ctrl-v to paste, click save on the Roll20 handout or whatever. This makes dealing with tables so much easier! You may need to go back and clean up the spacing or something after you have saved in roll20, but it's easy once the text and tables are already laid out. Also, if you make tables in this fashion I recommend placing a place holder ( I used a 0 ) in any empty table cells. Sometimes the text editor will shrink the table cell down until you type something in the cell. I'm on my phone right now, but I'll post a copy of my version of a character sheet done in the fashion David, from table top gaming, does on his YouTube tutorial videos. It may be semi obsolete since the recent update, but I still like having a "manual" character sheet, plus I like the rules linking to handouts.
I'm not sure if this text editing technique works with open office (or whatever the open source version of word is called), but I don't see why it wouldn't. The main thing is to save in rich text format. It transfers better to Roll20.
hope this helps.