browsevar: display the bytes-size rather than N/A when the format of the object is unknown or not applicable
Reported by Samuel GOUGEON (@sgougeon)
BUG DESCRIPTION:
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for example, the format of a compiled functions is meaningless, and N/A is listed for them in the "Dimension" column.
However, the byte-size of functions is retrieved. It is a pity to display it in tooltips rather than in clear in the column. N/A is not an info. The byte-size is.
It is obvious for a human that it is not strictly the same info. So it is
meaningless to "hide" it in a tooltip to not let thinking that it could be
taken as a "function format". Just display "# bytes"
In a general point of view, the maximum available infos should be displayed.
When infos can be _returned_, they must be fully homogeneous. But when they
are only displayed, they must be fully ergonomic.