save/load not working?

I thought this should work, but it doesn't:

using Graphs
using MetaGraphs

g = path_graph(5)
mg = MetaGraph(g, 3.0)
set_prop!(mg, :description, "This is a metagraph.")

savegraph("/tmp/test_graph.lg", mg)

mg1 = loadgraph("/tmp/test_graph.lg")

ERROR: LoadError: BoundsError: attempt to access 2-element Vector{SubString{String}} at index [3]
Stacktrace:
  [1] getindex
    @ ./array.jl:861 [inlined]
  [2] indexed_iterate
    @ ./tuple.jl:90 [inlined]
  [3] _parse_header(s::SubString{String})
    @ Graphs ~/.julia/packages/Graphs/zrMoC/src/persistence/lg.jl:62
  [4] loadlg(io::IOStream, gname::String)
    @ Graphs ~/.julia/packages/Graphs/zrMoC/src/persistence/lg.jl:104
  [5] loadgraph
    @ ~/.julia/packages/Graphs/zrMoC/src/persistence/lg.jl:147 [inlined]
  [6] #120
    @ ~/.julia/packages/Graphs/zrMoC/src/persistence/common.jl:15 [inlined]
  [7] open(::Graphs.var"#120#121"{String, LGFormat}, ::String, ::Vararg{String}; kwargs::Base.Pairs{Symbol, Union{}, Tuple{}, NamedTuple{(), Tuple{}}})
    @ Base ./io.jl:330
  [8] open
    @ ./io.jl:328 [inlined]
  [9] loadgraph
    @ ~/.julia/packages/Graphs/zrMoC/src/persistence/common.jl:14 [inlined]
 [10] loadgraph(fn::String)
    @ Graphs ~/.julia/packages/Graphs/zrMoC/src/persistence/common.jl:18
 [11] top-level scope
    @ untitled-55510ba3fa4677b8db7457446bdad39a:10

Is it something to do with the compressed format - savegraph(.. ... metagraph ... , compress=false) doesn't work either?

Using Graphs v1.7.0, MetaGraphs v0.7.1, Julia 1.7.

The stack trace points to src/persistence/lg.jl, especially _parse_header at line 62; start by reproducing the savegraph/loadgraph example with the listed Julia, Graphs, and MetaGraphs versions. Compare the generated .lg file with what loadlg expects, and consider the issue resolved when the example loads successfully without the BoundsError.