Thunderbird changing existing color, and occasionally font, from original messages in replies

Question

Hello,
Thunderbird keeps consistently changing text color (always) and font (sometimes, intermittently) when I reply to a message. I hope the attached images will make clear what I mean.
I have many e-mail exchanges where individuals involved use both font and color to make it instantly possible to distinguish who said what, and often in what order, based upon the font being specific to the individual and the color specific to the response given.
You will see in the attached screen shots that the original message contained two different fonts in dark blue colors. When I hit "Reply" the compose window switches all the text from the old messages to black. In this case it wouldn't matter much, but it can be very disorienting when you have an e-mail exchange going on that's got more participants all of whom use signature fonts and change either the font and/or color as the conversation progresses. Having everything "go black" removes essential context.
I also find it odd that when you place your cursor in the middle of existing text and open up a new line to insert your own material that the new material always mimics the last font that was in the material you've just "split open" to add your own reply. In virtually every other e-mail editor I've used when you place yourself in existing text and split it apart by hitting a return the opened area typically would use the font and font color you currently have specified in the compose window.
If there are settings I need to tweak to:
1. Force Thunderbird to maintain all existing fonts and font colors when replying to an existing e-mail message,
2. Get Thunderbird to use the font and font color I have chosen in the compose window any time I split existing quoted material to add new material,
I'd love to know what those settings are.

Answer 1

Matt,
I decided to do some experimentation with creating multiple messages and replies strictly within Gmail's web interface and then to reply to same from Thunderbird. After that, I attempted to start the same sort of chain strictly using Thunderbird to create the messages. The difference is pretty stark.
The first attachment is how the multiple fonts and colors that originated from Gmail show in Thunderbird's reading window. They are all correct here.
The second shows how the multiple fonts and colors that originated from Gmail show up when I reply from within Thunderbird. Again, all of those fonts and colors are maintained as sent and the font and color I designated in my Thunderbird options are what get used when composing the reply.
The last shows what happens when I sent a message created in Thunderbird with one font and color and then go to reply to it from within Thunderbird after having switched my default font and color choice for composition intentionally prior to replying. The font from the original message is retained in the reply, but the color is converted to what has been selected for composition. This suggests to me that Thunderbird is not retaining color information at each "level" within a reply. It has to have sent color information in the original message because it shows up in that color on receipt when reading (I didn't bother with a screen shot, but if you want one I can get one). When replying it is stripping or overwriting the color information from the original message and using the current compose color and applying it to everything in the window.
As far as I'm concerned, that's a bug.
Brian