empty template parameter (null default) inside html tag definition causes brace mismatch

[joshinils]

the text in above image

<div {{#if:{{{param|}}}|{{{param}}}|{{ATemplate|Template arg}}}}> div content </div>
<div {{#if:{{{param| }}}|{{{param}}}|{{ATemplate|Template arg}}}}> div content </div>
<div {{#if:{{{param|a}}}|{{{param}}}|{{ATemplate|Template arg}}}}> div content </div>

<div {{#if:{{{param|}}}|{{{param}}}|{{ATemplate|Template arg}} }}> div content </div>
<div {{#if:{{{param| }}}|{{{param}}}|{{ATemplate|Template arg}} }}> div content </div>
<div {{#if:{{{param|a}}}|{{{param}}}|{{ATemplate|Template arg}} }}> div content </div>

example from #83

The extra space between the two pairs of closing curly braces helps, but not all of the time – and usually there isn't one there it seems.

[joshinils]

It can't be another extension – I've now also installed this extension in my (almost) blank Insider's install, and all other extensions are disabled.

Just as with #78, it appears to match the |} instead of the overlapping }}} behind it.

the text in above image

{| <div {{#if:{{{param|}}}|{{{param}}}|{{ATemplate|Template arg}}}}> div content </div>
{| <div {{#if:{{{param| }}}|{{{param}}}|{{ATemplate|Template arg}}}}> div content </div>
{| <div {{#if:{{{param|a}}}|{{{param}}}|{{ATemplate|Template arg}}}}> div content </div>

{| <div {{#if:{{{param|}}}|{{{param}}}|{{ATemplate|Template arg}} }}> div content </div>
{| <div {{#if:{{{param| }}}|{{{param}}}|{{ATemplate|Template arg}} }}> div content </div>
{| <div {{#if:{{{param|a}}}|{{{param}}}|{{ATemplate|Template arg}} }}> div content </div>

{| <div {{#if:{{{param|}}}|{{{param}}}|{{ATemplate|Template arg}}}}> div content </div>  |}
{| <div {{#if:{{{param| }}}|{{{param}}}|{{ATemplate|Template arg}}}}> div content </div>  |}
{| <div {{#if:{{{param|a}}}|{{{param}}}|{{ATemplate|Template arg}}}}> div content </div>  |}

{| <div {{#if:{{{param|}}}|{{{param}}}|{{ATemplate|Template arg}} }}> div content </div>  |}
{| <div {{#if:{{{param| }}}|{{{param}}}|{{ATemplate|Template arg}} }}> div content </div>  |}
{| <div {{#if:{{{param|a}}}|{{{param}}}|{{ATemplate|Template arg}} }}> div content </div>  |}

[joshinils]

probably the same as #84?

[joshinils]

A workaround is inserting a space into the |} -> | }.