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How to get compatibility mode or notify ff browser of HTML4

PhilOsborn
PhilOsborn
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I manage an old but large and constantly changing commercial website. The site was originally done in HTML2 and has long been at HTML4, with no plans yet to move to HTML5, which would break huge amounts of code using <font> tags, etc.

I use "http://www.w3.org/TR/html4/loose.dtd"> at the top of the files, and it works fine with the latest Explorer in compatibility mode, but less well with other browsers, such as FF, where font sizes and colors, etc. are glitching.

Is there a way to force FF into the equivalent of IE's compatibility mode? Or to tell FF in the header to function as an HTML4 browser? </font>

I manage an old but large and constantly changing commercial website. The site was originally done in HTML2 and has long been at HTML4, with no plans yet to move to HTML5, which would break huge amounts of code using <font> tags, etc. I use <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> at the top of the files, and it works fine with the latest Explorer in compatibility mode, but less well with other browsers, such as FF, where font sizes and colors, etc. are glitching. Is there a way to force FF into the equivalent of IE's compatibility mode? Or to tell FF in the header to function as an HTML4 browser?

All Replies (1)

Gingerbread Man
Gingerbread Man
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What does the validator say about your site's markup and CSS?

You can trigger Quirks Mode rendering by omitting the DOCTYPE.

You really shouldn't have any issues "upgrading" to HTML5 if you don't use antiquated presentation tags like <font> and <center>.