Message text, or menus, toolbars etc?

You don't and can't know how your recipient will see it, unless you know all about his display size, resolution, choice of fonts and colours. If he sees your messages on multiple devices, particularly phones or tablets, chances are it'll be presented differently on each one. If he's using a decent email client on his computer(s) he may be able to override or ignore your settings. So part of your expectations is not attainable.

For menus etc, you don't need an add-on. You are welcome to learn and write the requisite css code. However for most of us, including myself, an add-on gives a much easier route to satisfaction.

For message text size, you need to set it under Tools|Options|Display|Formatting

I'd recommend you explore the Advanced settings too, to cater for the various encodings you encounter in your incoming email.

http://chrisramsden.vfast.co.uk/9_Type_sizes.html

Zenos, thank you for your reply. Unfortunately I have read those same comments before. In my mind, there shouldn't be an "add on" necessary to change the font size type of the entire interface of Thunderbird if desired. And to have to write "css code?" --- that's ridiculous!

No, I don't care what font and style my RECIPIENTS view my emails --- that's their prerogative. What I want to change is how I see everything on Thunderbird, from the interface to what I'm typing in an email. The font in Thunderbird for everything is so small it's ridiculous, and to not be able to change it is awful. What was/is Mozilla thinking?!

I may just totally bail on Thunderbird for this reason (I was an old Eudora user).  With all the complaints I notice, I would think Mozilla would fix this problem in Thunderbird and add the capability to change how the interface is viewed in the Thunderbird program without needing "add ons."  I am wary of downloading add-ons since several users have complained about conflicts in other areas of their computer usage.

So here's my plea to Mozilla --- Please fix this problem and make your Thunderbird email interface with larger default fonts!!!

But it's all adjustable.

In contrast with, say, Skype, on Windows; please tell me how to increase the size of the ridiculously small text in the user interface.

When I was upgraded to Windows 7 on a laptop with a comparatively high resolution display, I struggled to read much of the text. Even now, I do all the serious work in MS products (Office: Word, Excel, Outlook when I have to use it) on an external monitor where the lower resolution gives me a comfortable text size.

As far as I see it, Microsoft are steadily making Windows-based computers unusable. Thank goodness for Mozilla's products where you can actually set user interface font sizes.

Zenos, thank you again for your comment. If you claim Windows is the problem for making the typeface smaller in Thunderbird, I suppose that is possible, I don't know. I am running Windows 8.1. However, I still fault Mozilla for not making it easier to change the viewing interface. There's no excuse once the problem has been identified by so many Thunderbird users.

All right, so you say the "add-on" works to make fonts and interface adjustable. Unlike some other users of the add-on who have claimed it has caused problems on their computers, have you experienced no other problems after installing the add-on?

If you, like others, have experienced other problems with the add-on, then the add-on is not an adequate solution.

If you have experienced no problems with the add-on, and you think the add-on is the perfect solution, then can you please give me detailed instructions on downloading the add-on, and can you please give me a detailed step-by-step guide on how exactly I make the interface larger in Thunderbird with the add-on.

Thank you in advance for your assistance.

I use https://addons.mozilla.org/en-us/thunderbird/addon/theme-font-size-changer/ in both Firefox and Thunderbird, in both Windows and Linux, and am not aware of any problems associated with its use.

But I'm not clear yet if your issue is with menus and lists, or message text. You seemed to be talking about message text here: "I want to see what I type in a message the same as my recipient will read it!" but you don't need any add-ons to adjust that. So your references to add-ons suggest that in addition you are unhappy with menus and toolbars and perhaps the message list too.

Thanks again for trying, Zenos:

Here are "my issues" --- not only my complaints, but the same complaints many other users have mentioned about the Thunderbird email program. (My complaints may not be complete, since I have been only using the Thunderbird email program for nearly one week):

1) I would prefer that the entire default interface of the Thunderbird email program to be in a larger font and format. As it is, it's just too small --- and enough users have made that same comment. If Mozilla wants to make the interface and default font of the interface adjustable, that's fine, but Mozilla should make the adjustment easy, within the original Thunderbird email program, and not require an add-on.

2) If I format my outgoing email to appear in Times New Roman 12 point font, that's what I want to see typed when I write the email (not 8 font, which is barely readable, and how it appears in default).

Thanks. Once again, if you think the "add-on" is a sure-fire way to solve these problems, and you are quite sure the add-on will not cause any other problems with my computer and/or other programs, please: 1) direct me to the precise add-on download, and 2) give me specific step-by-step instructions within the add-on program to achieve my desired results.

Thank you, again, for your attention!

if you want it bigger use the tools Microsoft provided to make things larger.

Point 1, See Microsofts instructions to use your operating system features to solve your problem and make the interface larger. This has been around since Windows 3 because scaling and DPI are not new issues. http://blogs.windows.com/bloggingwindows/2013/07/15/windows-8-1-dpi-scaling-enhancements/

Point 2. Given that Thunderbird does not support point sizes in a font size specification. See the original link posted by Zenos, I think you have already specified your font in Pixels. Which is roughly 30% smaller than points. About the different between 8 and 10 or 12 points actually depending on screen resolution.

Point 3. No one is going to give you an iron clad guarantee. IF you want to drop your computer around for a few weeks of analysis and testing I can suggest I have or have not found errors in your configuration. I can not guarantee it will not crash and burn tomorrow. Nor can I assume the software I tested with is still there tomorrow. Any good anti virus updates daily at least.

As for a link to the add-on, that is referenced in Zenos last post on this thread. clicking the link provides all the information that is available.

Matt,

Thank you for your reply. Here are my problems with your solutions though:

1) I only want to make the interface larger in Thunderbird, not with other programs. With other programs the size is fine. It's only in Thunderbird that I would like the interface and font size appearance larger.

2) Mozilla may want to clarify the difference in it's pixels sizing and regular font sizing (points) and include a sizing comparison to make them more compatible (unless everything is moving to pixels and soon no one will be using points for font sizing, and in that case, the font sizing issue should be clarified).

3) I know you can't guarantee errors in configuration for "add-ons," and that's my point. I think interface appearance changes may be better as a function of the original Thunderbird email program and not as an "add-on."

Anyway, I think we've exhausted this discussion. I appreciate your efforts to help (Zenos and Matt). But I guess until Mozilla is willing to make these few changes in Thunderbird, I (and many others who have expressed the same frustration with these problems) will have to decide whether to: 1) accept these faults in Thunderbird, or 2) gravitate to another email program.

Thanks again for trying!

Reading between the lines, I believe your problem is the same as mine - when message is typed the font is too small and then suddenly gets larger when message is sent and appears in the Sent folder.

If the above is true, when you are about to type your message, hit "CTRL +" about 5 times then type your message. You can experiment with this until you find the right size font for you.

Then send it to yourself, if it looks OK your problem is solved.

You're just zooming the display of the text. Why not just set it right for you in the first place?

Tools|Options|Display|Formatting

Set the font type and size there. More here:

http://www.chrisramsden.vfast.co.uk/9_Type_sizes.html

Just as I posted previously: https://support.mozilla.org/en-US/questions/1019224#answer-626251

Forgive my ignorance, I can do Tools|Options|Display| but for the life of me I do not see anything called: Formatting

Ahhhh! Found Formatting! Sorry about that! I may try all that sometime but "CTRL +" works just fine for me right now and it is super easy. As you have probably ascertained, I need super-easy.

Thank you, Stardancer and Zenos for keeping this post "alive," but these still do not totally address my issue.

1) Yes, under "formatting" and "composition" I can equate what I'm seeing when I'm typing to match what I'm sending out in font size and type. I have chosen Times New Roman in "14" and chosen "large" under composition, and these seem to match up. Although this works, I think Mozilla should have an easier solution to "match" what one "sees" on the screen when typing an email to what is then "sent out."

2) What is not possible is to make the ENTIRE INTERFACE of Thunderbird LARGER in font. The interface of Thunderbird, in my opinion, and in many others' opinions by reading similar complaints, is just too small. Yes, one can make everything on one's computer larger by making everything larger in Windows. But I and others don't want everything we see on our computers larger, we just want the interface of Thunderbird a bit larger! If Mozilla could provide an option to increase the size of its interface a little, or increase the size of its interface as its default size, that would be very helpful, and that solution would satisfy many users who have communicated similar complaints about the Thunderbird email program.

Round we go again.

Interface text size: https://support.mozilla.org/en-US/questions/1019224#answer-626569

Yes, let's drop this issue (again). With all due respect, Zeno, your solution of using an "add-on" is unacceptable. Until Mozilla is willing to solve the problem by making it easier to change the font size of Thunderbird's ENTIRE INTERFACE, users will: 1) continue to complain about the issue, 2) will be dissatisfied with Thunderbird, and 3) may gravitate to other email programs.

I don't understand your prejudice against add-ons.

Create a folder named chrome in your profile.

In that folder, create a file named userChrome.css

Paste the following text into that file. Adjust the numbers to suit you. You may use points or pixels, but do adjust the values accordingly. Everything else's size is set in pixels in Thunderbird, so I do the same here for consistency. Some people have an unhealthy obsession with points on computer screens, where they are more or less meaningless.

/*
 * Do not remove the @namespace line -- it's required for correct functioning
 */
@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"); /* set default namespace to XUL */
 
/* 
 * Make all the default font sizes 12 px:
 */
* { font-size: 12px !important; }

Zenos, your instructions prove my point --- why should Thunderbird users have to go through "a process like you describe" simply to increase the interface font size for Thunderbird? It's silly! Many users are not "tech people" and want simpler solutions without "add-ons" and creating folders for this, and creating folders for that, and pasting this into that, blah, blah, blah. Face it, the capability should be built into the Thunderbird program with one button. The feature should be built into the Thunderbird program instead of being an "add-on." Add-ons to programs come with at least some risk of potential problems, and many people would probably prefer these "options" to be a part of the original program and not an add-on.

Also, as far as I can tell, users complaining about this issue, including myself, don't want to increase the interface font size of all Firefox, we just want to increase the interface font size of Thunderbird.

So, with all due respect, Zenos --- and believe me, I appreciate your efforts --- instead of stubbornly sticking to your position that this is an "easy fix" with an "add on," I suggest you direct your energy to Mozilla, by simply suggesting to them that they create an option built into the Thunderbird program to increase the Thunderbird interface font size. I am quite sure many users and potential users would appreciate that capability.

Thanks, again.

Are you suggesting that global change of font in applications is a commonly encountered feature? I'm still struggling with Microsoft programs that offer no possibility at all of adjusting the font, and yet here with Mozilla products I've shown you TWO methods, and you still consider Mozilla lacking?

Thunderbird and Firefox are adjusted separately and independently. Why do you assume adjusting one would affect the other?

Please... Mozilla... just put an option in the Thunderbird program (not an add-on) that increases the interface font size. Your users and potential users will appreciate it. As a matter of fact, In my humble opinion, if I were you, Mozilla, I would frankly just increase the DEFAULT original interface size... then you might not even need to make an option to increase it. :)

They will loose me as a user if they make the interface any bitter. It is right now. As for making accessibility options a part of the program. Do you use Microsoft's sticky keys? what about mouse keys?

If like most people you have never heard of them, you will understand why such a feature is not in the default interface. Simply most people do not need it and there a more options than the average user can find now. In Microsoft's case they put in the kitchen sink and no one actually knows what is in there it is so complex. In Mozilla's case they offer the base package which is in itself complex enough and a whole raft of add-ons to customize it you your liking. In the case of the add-on in question here, it is produced by Mozilla.

You apparently have a prejudice against add-ons. That is fine, but I seriously doubt with that approach that Mozilla products are for you as add-ons are integral to their extension. Many seriously necessary features are only available though the use of add-ons.