Contao

Are you talking about a "select menu"? I just created a "select menu", a "checkbox menu" and a "radio button menu" in the form generator of the Demo site (each time with a differen default option).

They all got rendered with their selected default-option. I can't find a bug here.

If you just hit the reload button, Firefox remembers your current settings and does not change the drop-down menu. Try to enter the URL into the address bar and then hit enter. Does this solve your problem?

After the Nina's answer I decide to do some test on my computer with Wampserver 2.
The result of my tests is very strange :|
1 - I upgrade a 2.6.7 (with demo site) version to a 2.7.3, I add a list menu, it's OK, the selected option is here.
2 - I install a fresh 2.7.3 (with demo site) add a list menu with the same options, the selected value is not here :(
3 - After that I decided to invert the databases, on my "updated" installation I put the fresh database, now the listmenu doesn't works...
4 - I decide to see 'tl_form_field' table. The records are the same on the two databases. Just the structure is different: fields are not on the same order.
5 - I don't understand :|

Hi Leo,

This morning, I continue my tests :)
I install 2 versions : 2.6.7 and 2.7.0, for each I import example_website.sql
Into the "Term paper submission" form I add a "select menu" with 3 options test1, test2, test3 and I set test2 as default.
I modify "system\modules\frontend\FormSelectMenu.php" I write on line 196 : print_r($arrOption);

The output :

With 2.6.7 :

Array
(
    [value] => test1
    [label] => test1
)
Array
(
    [value] => test2
    [label] => test2
    [default] => 1
)
Array
(
    [value] => test3
    [label] => test3
)
<select name="test" id="ctrl_13" class="select">
<option value="test1">test1</option>
<option value="test2" selected="selected">test2</option>
<option value="test3">test3</option>
</select>

With 2.7.0 :

Array
(
    [value] => test1
    [label] => test1
)
Array
(
    [value] => test2
    [label] => test2
    [default] => 1
)
Array
(
    [value] => test3
    [label] => test3
)
<select name="test" id="ctrl_12" class="select">
<option value="test1">test1</option>
<option value="test2">test2</option>
<option value="test3">test3</option>
</select>

As you can see " selected="selected" disappear on 2.7.0

After, I upgrade my 2.6.7 to 2.7.0 without re-import the site template.
Now this updated version is OK :

Array
(
    [value] => test1
    [label] => test1
)
Array
(
    [value] => test2
    [label] => test2
    [default] => 1
)
Array
(
    [value] => test3
    [label] => test3
)
<select name="test" id="ctrl_13" class="select">
<option value="test1">test1</option>
<option value="test2" selected="selected">test2</option>
<option value="test3">test3</option>
</select>

Strange isn't it ?

Just for complete: this problem is the same with "Radio button menu" and "Checkbox menu"

This one was really hard to figure out. It has something to do with the order of the fields of table tl_form_fields. If "value" comes before "options", it works like a charm. However, if "options" comes before "value", which is e.g. the case in installations prior to version 2.7, it does not.

I have overworked a couple of files and uploaded them here (system.zip). Please replace the files of your installation (2.7.3), run some tests and let me know if it works.

Many thanks Leo, my tests are OK.
It works like a charm :)